Air blast wave protection

ABSTRACT

Described embodiments include a system, device and method. A described device includes a layer of a first material configured to reflect a substantial portion of a specified incident air blast wave energy. The layer of the first material has an acoustic impedance substantially mismatched to air&#39;s acoustic impedance, and a thickness less than about 3 mm. The device includes a layer of a second material configured to attenuate a substantial portion of the specified incident air blast wave energy utilizing an inelastic response. At least a portion of a back surface of the first material is proximate to at least a portion of a front surface of the second material.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is related to and claims the benefit of theearliest available effective filing date(s) from the following listedapplication(s) (the “Related Applications”) (e.g., claims earliestavailable priority dates for other than provisional patent applicationsor claims benefits under 35 USC §119(e) for provisional patentapplications, for any and all parent, grandparent, great-grandparent,etc. applications of the Related Application(s)).

RELATED APPLICATIONS

For purposes of the USPTO extra-statutory requirements, the presentapplication constitutes a continuation-in-part of U.S. patentapplication Ser. No. 13/135,389, entitled WEARABLE AIR BLAST PROTECTIONDEVICE, naming Philip Andrew Eckhoff, Roderick A. Hyde, Muriel Y.Ishikawa, Jordin T. Kare, and Lowell L. Wood, Jr. as inventors, filedJun. 30, 2011, which is currently co-pending, or is an application ofwhich a currently co-pending application is entitled to the benefit ofthe filing date.

For purposes of the USPTO extra-statutory requirements, the presentapplication constitutes a continuation-in-part of U.S. patentapplication Ser. No. 13/135,390, entitled WEARABLE AIR BLAST PROTECTIONDEVICE HAVING AT LEAST TWO ATTENUATING REGIONS, naming Philip AndrewEckhoff, Roderick A. Hyde, Muriel Y. Ishikawa, Jordin T. Kare, andLowell L. Wood, Jr. as inventors, filed Jun. 30, 2011, which iscurrently co-pending, or is an application of which a currentlyco-pending application is entitled to the benefit of the filing date.

For purposes of the USPTO extra-statutory requirements, the presentapplication constitutes a continuation-in-part of U.S. patentapplication Ser. No. 13/135,401, entitled WEARABLE AIR BLAST PROTECTIONDEVICE HAVING AT LEAST TWO REFLECTIVE REGIONS, naming Philip AndrewEckhoff, Roderick A. Hyde, Muriel Y. Ishikawa, Jordin T. Kare, andLowell L. Wood, Jr. as inventors, filed Jun. 30, 2011, which iscurrently co-pending, or is an application of which a currentlyco-pending application is entitled to the benefit of the filing date.

The United States Patent Office (USPTO) has published a notice to theeffect that the USPTO's computer programs require that patent applicantsreference both a serial number and indicate whether an application is acontinuation or continuation-in-part. Stephen G. Kunin, Benefit ofPrior-Filed Application, USPTO Official Gazette Mar. 18, 2003, availableat http://www.uspto.gov.htm. The present Applicant Entity (hereinafter“Applicant”) has provided above a specific reference to theapplication(s) from which priority is being claimed as recited bystatute. Applicant understands that the statute is unambiguous in itsspecific reference language and does not require either a serial numberor any characterization, such as “continuation” or“continuation-in-part,” for claiming priority to U.S. patentapplications. Notwithstanding the foregoing, Applicant understands thatthe USPTO's computer programs have certain data entry requirements, andhence Applicant is designating the present application as acontinuation-in-part of its parent applications as set forth above, butexpressly points out that such designations are not to be construed inany way as any type of commentary or admission as to whether or not thepresent application contains any new matter in addition to the matter ofits parent application(s).

All subject matter of the Related Applications and of any and allparent, grandparent, great-grandparent, etc. applications of the RelatedApplications is incorporated herein by reference to the extent suchsubject matter is not inconsistent herewith.

BACKGROUND

The following is an excerpt from Tammie L. S. Benzinger et al.,Blast-Related Brain Injury: Imaging for Clinical and ResearchApplications: Report of the 2008 St. Louis Workshop, JOURNAL OFNEUROTRAUMA 26:2127, 2129 (December 2009) (Accessed Aug. 20, 2010, atwww.liebertonline.com/doi/pdf/10.1089/neu.2009.0885) (citationsomitted):

-   -   “It is important to have a basic understanding of the physics of        blast insult prior to developing any hypothesis regarding bTBI        mechanisms, countermeasures, or treatments. Understanding the        processes by which a blast event ultimately inflicts stresses at        the cellular and subcellular levels is also a prerequisite to        the design of proper animal model testing and interpretation of        results.    -   A blast event as considered here begins with a detonation, the        nearly instantaneous combustion of a liquid or solid explosive        material resulting in the generation of gaseous products at        extremely high pressure and temperature (˜150 k atm/˜2M psi,        ˜3000° K). The gaseous detonation products expand rapidly into        the surrounding atmosphere to about 3000-fold their original        volume, and are visible as a luminous fireball. Primary        fragmentation from the charge casing as well as dirt and ejecta        from buried charges will be carried with the fireball expansion        and are projected much further than the gaseous products. The        rapid expansion of the fireball drives a shockwave into the        surrounding air ahead of it. The combined violent expansion of        product gases and propagated shockwave constitute the blast flow        field.    -   The most distinctive feature of the air blast wave energy is the        shock front, through which there is a nearly instantaneous        change in all gas-dynamic conditions of the air (pressure,        density, flow velocity, and temperature). While the air blast        wave energy strength is often characterized exclusively in terms        of the peak blast overpressure, it is important to note that        this metric will usually refer to the static or side-on pressure        above ambient levels, which does not represent the loading        condition on a typical target. The static pressure is that        pressure which would be sensed by a surface aligned parallel to        the blastwave propagation, and hence does not experience the        kinetic energy component of the flow, which may be many-fold        higher than the static pressure component. If the same surface        were perpendicular to the blast, it would obstruct the flow and        be exposed to a much higher pressure of the reflected blast,        including both the static and dynamic (kinetic energy)        components. The actual stresses and waveform experienced at the        cellular level will depend on the transfer function for the        target, which is highly geometry- and material-dependent. These        distinctions regarding the incident blast flow conditions,        imparted loading, and cellular stresses have important        implications with regard to the mechanisms for blast injury, as        well as the proper simulation of blast in the laboratory,        Whereas the static pressure profile is an important component of        blast insult, it is by no means the only relevant energy        component, particularly for victims within the area of the        fireball, where kinetic energy of the flow is dominant.    -   The blast flow field exhibits energy in various modes in the        hydrodynamic domain, including material flow (kinetic energy),        static pressure, and internal energy (temperature). Due to the        shock front, the frequency content of the incident wave is        extremely high; indeed, the rate of the stress rise imparted to        tissue followed by rapid relaxation may be of as much concern        with regard to cellular damage as stress amplitude. Blast also        can propagate energy in the electromagnetic domain, although the        power spectrum is highly dependent on the device size and        configuration.”

FIG. 1 includes a graph 10 illustrating pressure versus time of anexample air blast wave energy 195. The example blast wave represents anair blast wave energy produced by a blast event, such as a detonatinghigh-order explosive. The graph represents time on a horizontal axis,and static or side-on pressure on a vertical axis expressed in units ofoverpressure P_(SO), or atmospheres above or below ambient pressure. Theair blast wave includes a shock front 22, which is typically travelingat a supersonic speed, is nearly vertical in its onset, and has athickness generally estimated at less than one micron. The shock frontis the leading edge of the air blast wave; it is the portion of the airblast wave transitioning from ambient atmospheric pressure to maximumoverpressure. The air blast wave includes a region of overpressure 24,and a region of underpressure 26. Humans exposed to air blast wavesgenerated by detonating high-order explosives are at risk forblast-related traumatic brain injury (bTBI), which is particularlyrelevant in current military engagements around the world, and whichsome consider the signature injury of the wars in Iraq and Afghanistan.

Air blast waves, like light, ultrasonic, and sonic waves, are reflectedat boundaries where there is a difference in acoustic impedances (Z) ofthe materials on each side of the boundary. This difference in Z iscommonly referred to as the impedance mismatch. The greater theimpedance mismatch, the greater the percentage of energy that will bereflected at the interface or boundary between one medium and another.Acoustic impedance (Z) values are generally expressed or used herein inMRayls unless otherwise indicated.

The fraction of the incident wave intensity that is reflected can bederived because particle velocity and local particle pressures must becontinuous across the boundary. When the acoustic impedances of thematerials on both sides of the boundary are known, the fraction of theincident wave intensity that is reflected can be calculated with theequation below. The value produced is known as the reflectioncoefficient (R). Multiplying the reflection coefficient by 100% yieldsthe calculated amount of energy reflected as a percentage of theoriginal energy.R=[(Z ₂ −Z ₁)/(Z ₂ +Z ₁)]²

Since the amount of reflected energy plus the transmitted energy mustequal the total amount of incident energy, the transmission coefficientis calculated by simply subtracting the reflection coefficient from one.

SUMMARY

An embodiment of the subject matter described herein includes an airblast wave protection device. The device includes a layer of a firstmaterial shaped and configured to reflect a substantial portion of aspecified incident air blast wave energy. The layer of the firstmaterial has (i) an acoustic impedance substantially mismatched to theacoustic impedance of air, and (ii) a layer thickness less than about 3mm. The device includes a layer of a second material shaped andconfigured to attenuate a substantial portion of the specified incidentair blast wave energy transmitted through the layer of the firstmaterial utilizing an inelastic response. The layer of the firstmaterial includes a front surface and a back surface, and the layer ofthe second material includes a front surface and a back surface. Atleast a portion of the back surface of the layer of the first materialis proximate to at least a portion of the front surface of the layer ofthe second material. In an embodiment, the device may include a labelindicating use of the device is limited to a single exposure to thespecified incident air blast wave energy. In an embodiment, the devicemay include an indicator configured to provide a human-perceivableindication that the device has been exposed to air blast wave energy. Inan embodiment, the device may include a spall liner shaped andconfigured to restrain at least one fragment broken from of the layer ofthe first material by the specified incident air blast wave energy. Inan embodiment, the device may include a layer of a ballistic materialshaped and configured to substantially attenuate energy of an objectimpacting the exterior portion of the human body. In an embodiment, thedevice may include a retaining apparatus configured to hold theproximate layer of a first material and the layer of the second materialadjacent to the exterior portion of the human body.

An embodiment of the subject matter described herein includes a methodof designing a wearable air blast wave energy protection device. Themethod includes computer modeling is at least two candidate reflectivematerials for a first human-protective and primarily reflective responseto a specified incident air blast wave energy. The computer modeling ofthe at least two candidate reflective materials is at least partiallybased on respective acoustic impedances of the at least two candidatereflective materials to the specified incident air blast wave energy.The respective acoustic impedances of the at least two candidatereflective materials are each substantially mismatched to the acousticimpedance of air. The method includes selecting a layer of a firstmaterial in response to the computer modeling of the at least twopossible layers of reflective material. The method includes computermodeling at least two candidate attenuative materials for a secondhuman-protective and primarily attenuative response to the specifiedincident air blast wave energy transmitted through the selected layer ofthe first material. The computer modeling of the at least two candidateattenuative materials is at least partially based on respectiveinelastic responses of the two candidate attenuative materials to thespecified incident air blast wave energy transmitted through theselected layer of the first material. The method includes selecting alayer of a second material in response to the computer modeling of atleast two candidate attenuative materials. The method includeselectronically maintaining informational data corresponding to theselected layer of the first material and the selected layer of thesecond material. In an embodiment, the method may include computermodeling at least two candidate methods of joining the layer of thefirst material and the layer of the second material. The computermodeling is at least partially based on an attribute of (i) thespecified incident air blast wave energy, and an attribute of either(ii) the first material relative to the specified incident air blastwave energy or (iii) the second material to the specified incident airblast wave energy. The method may include selecting an method of joiningin response to the computer modeling of at least two candidate methodsof joining. In an embodiment, the method may include electronicallytransmitting the informational data to a person or another machine.

An embodiment of the subject matter described herein includes a methodof manufacturing a wearable air blast wave energy protection device. Themethod includes receiving a layer of a first material selected toprovide a first reflective response to a specified incident air blastwave energy. The first material selected at least partially based on afirst acoustic impedance of the first material to the specified incidentair blast wave energy, and on a substantial mismatch between the firstacoustic impedance and the acoustic impedance of air. The methodincludes receiving a layer of a second material selected to provide asecond attenuative response to the specified incident air blast waveenergy transmitted through the first material. The second materialselected at least partially based on an inelastic response of the secondmaterial to the specified incident air blast wave energy transmittedthrough the layer of the first material. The method includes joining atleast a portion of the first material and at least a portion of thesecond material. The joining selected at least partially based on anattribute of the layer of the first material, an attribute of the layerof the second material, or an attribute of the specified incident airblast wave energy transmitted through the layer of the first material.

In an embodiment, the method may include shaping the layer of the secondmaterial into a configuration suitable for wearing proximate to theexterior portion of the human body. In an embodiment, the method mayinclude shaping the joined layer of the first material and the layer ofa second material into a layered physical form configured oruser-configurable for wearing proximate to the exterior portion of thehuman body. In an embodiment, the method may include shaping the joinedlayer of the first material and the layer of the second material into aphysical form configured or user-configurable for wearing proximate tothe exterior portion of the human body with the second layer proximateto the exterior portion of the human body. In an embodiment, the methodmay include coupling at least a portion of the layer of the firstmaterial or the layer of the second material to a retaining strapconfigured to removably secure the joined layer of the first materialand layer of the second material proximate to the exterior portion ofthe human body. In an embodiment, the method may include attaching thejoined layer of the first material and the layer of the second materialto a carrier shaped and configured to be secured proximate to theexterior portion of the human body.

An embodiment of the subject matter described herein includes a method.The method includes interposing between a blast event generating an airblast wave energy and the exterior portion of the human body a layer ofa first material positioned to initially receive a specified incidentair blast wave energy, the layer of the first material is shaped andconfigured to reflect a substantial portion of the specified incidentair blast wave energy. The layer of first material has an acousticimpedance substantially mismatched to the acoustic impedance of air anda layer thickness less than about 3 mm. The method includes interposingbetween the blast event generating an air blast wave energy and theexterior portion of the human body a layer of second material positionedto receive at least a portion of the air blast wave energy transmittedthrough the first material. The layer of the second material is shapedand configured to attenuate a substantial portion of the specifiedincident air blast wave energy transmitted through the layer of thefirst material utilizing an inelastic response, and shaped andconfigured for wearing proximate to the exterior portion of the humanbody. The layer of the first material includes a front surface and aback surface, the layer of the second material includes a front surfaceand a back surface, and at least a portion of the back surface of thelayer of the first material is proximate to at least a portion of thefront surface of the layer of the second material. In an embodiment, themethod includes substantially reflecting a portion the specifiedincident air blast wave energy utilizing the layer of the firstmaterial. In an embodiment, the method includes substantiallyattenuating at least a portion of the specified incident air blast waveenergy transmitted through the layer of the first material utilizing aninelastic response of the layer of the second material.

An embodiment of the subject matter described herein includes a device.The device includes a layer of a ballistic material shaped andconfigured to substantially attenuate energy of an object impacting ahuman head. The device also includes a layer of a first material shapedand configured to reflect a substantial portion of a specified incidentair blast wave energy. The layer of the first material has an acousticimpedance substantially mismatched to the acoustic impedance of air anda layer thickness less than about 3 mm. The device also includes a layerof a second material shaped and configured to attenuate a substantialportion of the specified incident air blast wave energy transmittedthrough the layer of the first material utilizing an inelastic response,and shaped and configured for wearing proximate to the human head. In anembodiment, the layer of the ballistic material includes a front surfaceand a back surface, the layer of the first material includes a frontsurface and a back surface, and the layer of the second materialincludes a front surface and a back surface. At least a portion of theinterior surface of the layer of the ballistic material is proximate tothe front surface of the layer of the first material, and at least aportion of the back surface of the layer of the first material isproximate to at least a portion of the front surface of the layer of thesecond material. In an embodiment, the layer of the ballistic materialincludes a front surface and a back surface, the layer of the firstmaterial includes a front surface and a back surface, the layer of thesecond material includes a front surface and a back surface. At least aportion of the back surface of the layer of the first material isproximate to the front surface of the layer of the ballistic material,and at least a portion of the back surface of the layer of the ballisticmaterial is proximate to at least a portion of the front surface of thelayer of the second material. In an embodiment, the layer of theballistic material includes a front surface and a back surface, thelayer of the first material includes a front surface and a back surface,and the layer of the second material includes a front surface and a backsurface. At least a portion of the back surface of the layer of thefirst material is proximate to the front surface of the layer of asecond material, and at least a portion of the back surface of the layerof the second material is proximate to at least a portion of the frontsurface of the layer of the ballistic material.

The foregoing summary is illustrative only and is not intended to be inany way limiting. In addition to the illustrative aspects, embodiments,and features described above, further aspects, embodiments, and featureswill become apparent by reference to the drawings and the followingdetailed description.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 includes a graph illustrating pressure vs. time of an example airblast wave energy 195;

FIG. 2 illustrates an example environment in which embodiments may beimplemented;

FIG. 3 illustrates a classical stress vs. strain plot for a typicalmaterial;

FIG. 4A illustrates a cross-sectional view of an alternative embodimentof the device of FIG. 2;

FIG. 4B illustrates a cross-sectional view of another alternativeembodiment of the device 101 of FIG. 2;

FIG. 5 illustrates a cross-sectional view an alternative embodiment ofthe device of FIG. 2;

FIG. 6 illustrates an alternative embodiment a cross-sectional view analternative embodiment of the device 101 of FIG. 2;

FIG. 7 illustrates a cross-sectional view of an alternative embodimentof the device of FIG. 2;

FIG. 8 illustrates an example operational flow 300;

FIG. 9 illustrates alternative embodiments of the reflection modelingoperation of the operational flow 300 of FIG. 8;

FIG. 10 illustrates alternative embodiments of the reflective materialselecting operation of the operational flow of FIG. 8;

FIG. 11 illustrates alternative embodiments of the attenuation modelingoperation 330 of the operational flow of FIG. 8;

FIG. 12 illustrates alternative embodiments of the attenuation modelingoperation 330 of the operational flow of FIG. 8;

FIG. 13 illustrates alternative embodiments of the attenuation modelingoperation 330 of the operational flow of FIG. 8;

FIG. 14 illustrates alternative embodiments of the attenuation materialselecting operation of the operational flow of FIG. 8;

FIG. 15 illustrates alternative embodiments of operational flow of FIG.8;

FIG. 16 illustrates alternative embodiments of the storage operation ofthe operational flow of FIG. 8;

FIG. 17 illustrates an example operational flow in which embodiments ofmanufacturing a wearable air blast wave energy protection device may beimplemented;

FIG. 18 illustrates alternative embodiments of the operational flow ofFIG. 17;

FIG. 19 illustrates an example operational flow;

FIG. 20 illustrates alternative embodiments of the operational flow ofFIG. 19;

FIG. 21 illustrates an environment that includes a cross-sectional viewof an example device;

FIG. 22 illustrates a cross-sectional view of an example wearable airblast wave energy protection device;

FIG. 23 illustrates an alternative embodiment of the device;

FIG. 24 illustrates an example operational flow;

FIG. 25 illustrates alternative embodiments of the operational flow ofFIG. 24;

FIG. 26 illustrates alternative embodiments of the operational flow ofFIG. 24;

FIG. 27 illustrates an example operational flow;

FIG. 28 illustrates an alternative embodiment of the operational flow ofFIG. 27;

FIG. 29 illustrates an example operational flow 1000;

FIG. 30 illustrates alternative embodiments of the operational flow ofFIG. 29;

FIG. 31 illustrates an environment that includes an example device;

FIG. 32 illustrates a cross-sectional view of an example wearable airblast wave energy protection device;

FIG. 33 illustrates a cross-sectional view of an alternative embodimentof the wearable air blast wave energy protection device;

FIG. 34 illustrates an example operational flow;

FIG. 35 illustrates alternative embodiments of the operational flow ofFIG. 34;

FIG. 36 illustrates alternative embodiments of the operational flow ofFIG. 34;

FIG. 37 illustrates an example operational flow 1500;

FIG. 38 illustrates an alternative embodiment of the operational flow ofFIG. 37;

FIG. 39 illustrates an example operational flow;

FIG. 40 illustrates alternative embodiments of the operational flow ofFIG. 39;

FIG. 41 illustrates an environment that includes an example device;

FIG. 42 illustrates a cross-sectional view of an example wearable airblast wave energy protection device;

FIG. 43 illustrates a cross-sectional view of an alternative embodimentof an wearable air blast wave energy protection device;

FIG. 44 illustrates an example operational flow 2100;

FIG. 45 illustrates alternative embodiments of the operational flow ofFIG. 44;

FIG. 46 illustrates alternative embodiments of the operational flow ofFIG. 44;

FIG. 47 illustrates an example operational flow;

FIG. 48 illustrates an alternative embodiment of the operational flow ofFIG. 47;

FIG. 49 illustrates an example operational flow;

FIG. 50 illustrates alternative embodiments of the operational flow ofFIG. 49; and

FIG. 51 illustrates an environment that includes example device.

DETAILED DESCRIPTION

In the following detailed description, reference is made to theaccompanying drawings, which form a part hereof. In the drawings,similar symbols typically identify similar components, unless contextdictates otherwise. The illustrated embodiments described in thedetailed description, drawings, and claims are not meant to be limiting.Other embodiments may be utilized, and other changes may be made,without departing from the spirit or scope of the subject matterpresented here.

FIG. 2 illustrates an example environment 100 in which embodiments maybe implemented. The environment includes a cross-sectional view of ahuman body 105 having an exterior body part portion 106, which may forexample include a head, leg, arm, trunk, or pelvis. The environmentincludes a blast event 193 creating an air blast wave 195 has an energypropagating across space from the blast event and illustrated asincident air blast wave energy 197-I. For example, an air blast wave mayinclude a shockwave originated by high explosive. For example, an airblast wave may include a range of overpressures occurring over a veryshort period of time. For example, an air blast wave may include anacoustic wave moving at or close to the speed of sound. For example, anincident air blast wave energy may include a wave traveling from itsblast source and toward a receiving human body, such as the incident airblast wave energy 197-I traveling from the blast event 193 toward thehuman body 105. While the air blast wave energy 197-I is schematicallyillustrated by a single line in FIG. 2, in a typical combat situationthe air blast wave energy will envelop most or all of the exterior bodypart portion of the human body, for example, such as a helmet or chestpad.

The environment illustrated includes a cross-sectional view of an airblast wave energy protection device 101. In an embodiment, the air blastwave energy protection device is wearable in a combat situation. Theenvironment illustrated includes an air gap 198 between the exteriorbody part portion 106 and the device 101. In an embodiment, the air gapmay be approximately zero.

The air blast wave energy protection device 101 includes a layer of afirst material 110 having a thickness 116 and a layer of a secondmaterial 120 having a thickness 126. The layer of a first material isshaped and configured to reflect a substantial portion of a specifiedincident air blast wave energy 197-I. For example, “configured” mayinclude designed, arranged, set up, shaped, optimized, tuned, adapted,capable of, or with a view to. For example, the specified incident airblast wave energy may be described at least in part by an overpressure,or a range of overpressures. For example, the specified incident airblast wave energy may be described at least in part by a velocity. Forexample, the specified incident air blast wave energy may be describedat least in part by a shock front.

The layer of the first material 110 has (i) an acoustic impedancesubstantially mismatched to the acoustic impedance of air. The acousticimpedance of air is approximately 0.0004. In an embodiment for example,carbon fiber has a range of acoustic impedances between approximately3.3 to 40 depending on specific structure, which in this embodiment isconsidered substantially mismatched to the acoustic impedance of air. Inan embodiment for example, aluminum has an acoustic impedance of 17,which in this embodiment is considered substantially mismatched to theacoustic impedance of air. In an embodiment for example, zinc has anacoustic impedance of 29.6, which in this embodiment is consideredsubstantially mismatched to the acoustic impedance of air. In anembodiment for example, steel has an acoustic impedance of 46, which inthis embodiment is considered substantially mismatched to the acousticimpedance of air.

The layer thickness of the first material 110 is less than about 3 mm.In an embodiment, a layer of first material having a thickness of atleast approximately the mean free path of air (0.066 microns, sometimesapproximated as 1 micron) would be theoretically expected to reflect asubstantial portion of the specified incident air blast wave energy197-I. However, because the blast wave may not have point sourcecharacteristics due to irregularities in the explosive or a positioningof the explosive, or due to irregularities in the path of the air blastwave energy such as buildings or armored vehicles, in an alternativeembodiment, a layer of the first material that is approximately oneorder of magnitude thicker (approximately 10-15 times) than the meanfree path of air is expected to reflect a substantial portion of thespecified incident air blast wave energy. In an embodiment, the layer ofthe first material may include a rigid layer of the first material. Forexample, a rigid layer of the first material may not be deflected by thespecified air blast wave energy. For example, the rigid layer of thefirst material may include a rigid layer of the first material that doesnot substantially bend, deform, or change shape in response to thespecified air blast wave energy. In an embodiment, the rigid layer ofthe first material may be deflected by the specified air blast waveenergy. For example, the layer of the first material may include aflexible layer of the first material that substantially bends, deforms,or changes shape in response to the specified air blast wave energy. Inan embodiment, the layer of the first material may include a non-rigidlayer. For example, the non-rigid layer of the first material may bedeflectable by the specified air blast wave energy. In an embodiment,the layer of the first material may be at least substantially destroyedby the energy of the specified air blast wave energy.

The layer of a second material 120 is shaped and configured to attenuatea substantial portion of the specified incident air blast wave energy197-I transmitted through the layer of the first material 110. Theattenuation utilizes an inelastic response to attenuate the specifiedincident air blast wave energy. For example, an inelastic response mayinclude a crumpling response, a crushing response, or a plastic flowresponse. The portion of specified incident air blast wave energy 197-Itransmitted through the layer of the first material 110 and that fallson the front surface 122 of the layer of the second material isillustrated as air blast wave energy 197-T.

For example, the air blast wave energy 197-T is the portion of thespecified incident air blast wave energy 197-I that passes through thelayer of the first material and is transmitted from the back surface 114of the layer of the first material. The portion of the air blast waveenergy 197-T that is transmitted through the layer of the secondmaterial 120 and toward the exterior body part portion 106 isillustrated as air blast wave energy 197-H. For example, the air blastwave energy 197-H is the portion of the air blast wave energy 197-T thatpasses through the layer of the second material and is transmitted fromthe back surface 124 of the layer of the second material. The layer ofthe second material is shaped and configured for wearing proximate tothe exterior portion 106 of the human body 105. In an embodiment, thespecified incident air blast wave energy transmitted 197-T from thelayer of the first material includes that portion of the specifiedincident air blast wave energy 197-I transmitted across an interfaceformed by the proximate 180 a back surface 114 of the layer of the firstmaterial 110 and a front surface 122 of the layer of the second material120. In an embodiment, a layer of an intermediate material (notillustrated) may be interposed between the back surface of the layer ofthe first material and the front surface of the layer of the secondmaterial. In such an embodiment, the specified incident air blast waveenergy transmitted through the layer of the first material would includethe specified incident air blast wave energy transmitted through thelayer of the first material and the interposed layer.

As used herein for example, “elastic” may include capable of resumingoriginal shape after a stretching or compression. As used herein forexample, “inelastic” may include lacking elasticity or not elastic(e.g., plastic), i.e., having a shape altered after a stretching orcompression. As used herein for example, attenuation “utilizing aninelastic response” may include utilizing an attenuation achievedprimarily by an inelastic response with other properties of the layer ofa second material supplying a significant attenuation or absorption ofthe specified incident air blast wave energy transmitted through thelayer of the first material. As used herein for example, “utilizing aninelastic response” may include employing an inelastic response. As usedherein for example, “utilizing an inelastic response” may includeutilizing an inelastic transaction. An inelastic response may includefor example, a plastic flow or fracture.

In the air blast wave energy protection device 101, the layer of thefirst material 110 includes a front surface 112 and the back surface114, the layer of the second material 120 includes the front surface 122and a back surface 124. At least a portion of the back surface of thelayer of the first material is proximate to at least a portion of thefront surface of the layer of the second material.

FIG. 3 illustrates a classical stress vs. strain plot 200 showing alinear elastic zone 210, an elastic/plastic transition zone 220, a crushplateau zone 230, and a densification zone 240 for a typical material.The initial linear elastic zone illustrates the region where a typicalmaterial is capable of resuming original shape after a stretching orcompression in response to an applied elastic stress σ between 0 andσ_(p1). The crush plateau zone (which may also be called an inelastic orplastic deformation zone) illustrates the typical material lackingelasticity or is not elastic, i.e., not capable of resuming originalshape after a stretching or compression in response to an applied yieldstress σ_(y)≧σ_(p1).

In a first phase of application of increasing stress, the typicalmaterial has an initial elastic regime illustrated by the relativelysteeply rising line of the linear elasticity zone 210. In a second phaseof application of increasing stress, the typical material has a plateauregime illustrated by the relatively horizontal line of the crushplateau zone 230. The load-to-crush ratio (or crush strength profile, orcrush profile) remains relatively constant in the crush plateau zone.This document uses “inelastic response” to describe a response of thetypical material to an applied yield stress σ_(y) in the crush plateauregion. As used herein for example, an “inelastic response” may includean inelastic transformation. As used herein for example, an “inelasticresponse” may include an inelastic crushing or an inelastic crushresponse. As used herein for example, an “inelastic response” mayinclude an inelastic transaction. As used herein for example, an“inelastic response” may include an inelastic transformation. As usedherein for example, an “inelastic response” may include a crushingresponse. As used herein for example, an “inelastic response” mayinclude an elasto-plastic deformation. In a third phase of theapplication of increasing applied stress, the typical material has aregime illustrated by the increasingly vertical line of thedensification zone 240. The densification zone may also reflect a “lockup regime” of a material.

Returning to FIG. 2, in an embodiment, the layer of the first material110 includes a layer of a first material shaped and configured toreflect a substantial portion of the shock front 22 of a specifiedincident air blast wave energy 197-I. The shock front is illustrated inFIG. 1. In an embodiment, the layer of the first material may bedemolished by the shock front and rendered at least substantiallyineffective to reflect a remainder of the region of overpressure 24 ofthe incident air blast wave energy. In an embodiment, the layer of thefirst material may remain partially or substantially intact afterpassage of the shock front and remain effective to reflect at least aportion of the remainder of the region of overpressure 24 of theincident air blast wave energy. The layer of the first material has (i)an acoustic impedance substantially mismatched to the acoustic impedanceof air, and (ii) a layer thickness 116 less than about 3 mm. In anembodiment, the layer of the first material includes a layer of a firstacoustic reflective material shaped and configured to reflect asubstantial portion of a specified incident air blast wave energy. Thelayer of the first material has (i) an acoustic impedance substantiallymismatched to the acoustic impedance of air, and (ii) a layer thicknessless than about 3 mm. In an embodiment, the layer of the first materialincludes a layer of a first material having (i) a calculated reflectioncoefficient to a specified incident air blast wave energy of at least99% (99% reflected, 1% transmitted), (ii) an acoustic impedancesubstantially mismatched to the acoustic impedance of air, and (iii) alayer thickness less than about 3 mm. The reflection coefficient iscalculated using the formulaR=[(Z ₂ −Z ₁)/(Z ₂ +Z ₁)]²In an embodiment, the layer of the first material includes a layer of afirst material shaped and configured to reflect at least 99% of a shockfront of a specified incident air blast wave energy and having (i) anacoustic impedance substantially mismatched to the acoustic impedance ofair, and (ii) a layer thickness less than about 3 mm. In an embodiment,the layer of the first material includes a layer of a first materialhaving (i) a calculated reflection coefficient to a specified incidentair blast wave energy of at least 75% (75% reflected, 25% transmitted),and (ii) a layer thickness less than about 3 mm. In an embodiment, thelayer of the first material includes a layer of a first material shapedand configured to reflect at least 75% of a shock front of a specifiedincident air blast wave energy and having (i) an acoustic impedancesubstantially mismatched to the acoustic impedance of air, and (ii) alayer thickness less than about 3 mm. In an embodiment, the layer of thefirst material includes a layer of a first material having (i) acalculated reflection coefficient to a specified incident air blast waveenergy of at least 50% (50% reflected, 50% transmitted), and (ii) alayer thickness less than about 3 mm. In an embodiment, the layer of thefirst material includes a layer of a first material shaped andconfigured to reflect at least 50% of a shock front of a specifiedincident air blast wave energy and having (i) an acoustic impedancesubstantially mismatched to the acoustic impedance of air, and (ii) alayer thickness less than about 3 mm. In an embodiment, the layer of thefirst material includes a layer of a first material having (i) acalculated reflection coefficient to a specified incident air blast waveenergy of at least 25%, and (ii) a layer thickness less than about 3 mm.In an embodiment, the layer of the first material includes a layer of afirst material shaped and configured to reflect at least 25% of a shockfront of a specified incident air blast wave energy and having (i) anacoustic impedance substantially mismatched to the acoustic impedance ofair, and (ii) a layer thickness less than about 3 mm. In an embodiment,the layer of the first material includes a layer of a first materialhaving (i) a calculated reflection coefficient to a specified incidentair blast wave energy of at least 10%, and (ii) a layer thickness lessthan about 3 mm. In an embodiment, the layer of the first materialincludes a layer of a first material shaped and configured to reflect atleast 10% of a shock front of a specified incident air blast wave energyand having (i) an acoustic impedance substantially mismatched to theacoustic impedance of air, and (ii) a layer thickness less than about 3mm. In an embodiment, the layer of the first material includes a layerof a first material having (i) a calculated reflection coefficient to aspecified incident air blast wave energy of at least 5%, and (iii) alayer thickness less than about 3 mm. In an embodiment, the layer of thefirst material includes a layer of a first material shaped andconfigured to reflect at least 5% of a shock front of a specifiedincident air blast wave energy and having (i) an acoustic impedancesubstantially mismatched to the acoustic impedance of air, and (ii) alayer thickness less than about 3 mm.

In an embodiment, the layer of the first material 110 includes a layerof a first material shaped and configured to reflect a substantialportion of a frequency spectrum or profile of the specified incident airblast wave energy 197-I. The layer of the first material has (i) anacoustic impedance substantially mismatched to the acoustic impedance ofair, and (ii) a layer thickness less than about 3 mm. In an embodiment,the layer of the first material includes a layer of a first materialshaped and configured to reflect a substantial portion of a specifiedincident combat high explosive air blast wave energy. The layer of thefirst material has (i) an acoustic impedance substantially mismatched tothe acoustic impedance of air, and (ii) a layer thickness less thanabout 3 mm.

In an embodiment, the layer of the first material 110 includes a layerof a first material shaped and configured to reflect a substantialportion of a specified incident air blast wave energy 197-I. The layerof the first material has (i) an acoustic impedance substantiallymismatched to the acoustic impedance of air, and (ii) a layer thickness116 less than about 2 millimeters. In an embodiment, the layer of thefirst material includes a layer of a first material shaped andconfigured to reflect a substantial portion of a specified incident airblast wave energy. The layer of the first material has (i) an acousticimpedance substantially mismatched to the acoustic impedance of air, and(ii) a layer thickness less than about 1.5 millimeters. In anembodiment, the layer of the first material includes a layer of a firstmaterial shaped and configured to reflect a substantial portion of aspecified incident air blast wave energy. The layer of the firstmaterial has (i) an acoustic impedance substantially mismatched to theacoustic impedance of air, and (ii) a layer thickness less than about1.0 millimeters. In an embodiment, the layer of the first materialincludes a layer of a first material shaped and configured to reflect asubstantial portion of a specified incident air blast wave energy. Thelayer of the first material has (i) an acoustic impedance substantiallymismatched to the acoustic impedance of air, and (ii) a layer thicknessless than about 500 microns. In an embodiment, the layer of the firstmaterial 110 includes a layer of a first material shaped and configuredto reflect a substantial portion of a specified incident air blast waveenergy. The layer of the first material has (i) an acoustic impedancesubstantially mismatched to the acoustic impedance of air, and (ii) alayer thickness less than about 100 microns. In an embodiment, the layerof the first material includes a layer of a first material shaped andconfigured to reflect a substantial portion of a specified incident airblast wave energy. The layer of the first material has (i) an acousticimpedance substantially mismatched to the acoustic impedance of air, and(ii) a layer thickness less than about 10 microns.

In an embodiment, the layer of the first material 110 includes a layerof a first material shaped and configured to reflect a substantialportion of a specified incident air blast wave energy 197-I. The layerof the first material has (i) an acoustic impedance substantiallymismatched to the acoustic impedance of air, and (ii) a layer thicknessminimized to a minimum thickness providing a selected level ofreflection of the specified incident air blast wave energy. In anembodiment for example, the layer thickness of the layer of the firstmaterial is minimized while achieving a selected level of reflection ofthe specified incident air blast wave energy, such as a −3 db or −5 dblevel of reflection of the specified incident air blast wave energy. Forexample, the layer thickness of the first material may be minimized to athickness that is approximately one order of magnitude thicker(approximately 10-15 times) than the mean free path of air is expectedto reflect a substantial portion of the specified incident air blastwave energy. In an embodiment, the layer of the first material includesa layer of a first material includes (a) a first reflective-regionshaped and configured to reflect a substantial portion of a specifiedincident air blast wave energy. The first reflective-region has (i) anacoustic impedance substantially mismatched to the acoustic impedance ofair, and (ii) a layer thickness less than about 3 millimeters. The layerof the first material includes (b) a substrate region (not illustrated)shaped and configured to physically support the first reflective-region.

FIG. 4A illustrates a cross-sectional view of an alternative embodimentof the device 101 of FIG. 2. In the alternative embodiment, the layer ofthe first material 110 is shaped and configured to reflect a substantialportion of a specified incident air blast wave energy 197-I and has alayer thickness 116 less than about 3 mm. The layer of the firstmaterial includes a pair of reflective-regions. A firstreflective-region 110A of the pair of regions has a first acousticimpedance Z₁ substantially mismatched to the acoustic impedance of airZ_(A). A second reflective-region 110B of the pair of regions has asecond acoustic impedance Z₂ substantially dissimilar from the firstacoustic impedance. In an embodiment, the specified incident air blastwave energy 197-T firstly arrives as the first reflective region andsecondly arrives at the second acoustic region. The first reflectiveregion includes a front surface 112A and a back surface 114A, the secondreflective region includes a front surface 112B and a back surface 114B,and at least a portion of the back surface of the layer of the firstmaterial is proximate 130A to at least a portion of the front surface ofthe layer of the second material. In an alternative embodiment, the pairof reflective regions 110A and 110B may be positioned side-by-side witheach occupying the full thickness 116 of the layer of first material andoriented to present both regions in parallel to the specified incidentair blast wave energy 197-I rather than in series as illustrated in FIG.4A. For example, see FIG. 23 illustrating a layer of a second material720 having pairs of regions positioned side-by-side, or FIG. 43illustrating a layer of a first material 2010 having pairs of regionspositioned side-by-side. In this embodiment, the specified incident airblast wave energy arrives substantially simultaneously at the firstreflective region and the second acoustic region.

Continuing with FIG. 4A, in such alternative embodiment, multiple pairsof the reflective regions 110A and 110B may comprise the layer of thefirst material. In an embodiment, the layer of the first material isshaped and configured to reflect a substantial portion of a specifiedincident air blast wave energy and has a layer thickness less than about3 mm. The layer of the first material includes a pair ofreflective-regions. A first reflective-region of the pair of regions hasa first acoustic impedance Z₁ substantially mismatched to the acousticimpedance of air Z_(A), and a second reflective-region of the pair ofregions has a second acoustic impedance Z₂ substantially dissimilar fromthe first acoustic impedance. In this embodiment, Z₁>Z₂. In anembodiment, the layer of the first material is shaped and configured toreflect a substantial portion of a specified incident air blast waveenergy and has a layer thickness less than about 3 mm. The layer of thefirst material includes a pair of reflective-regions. A firstreflective-region of the pair of regions has a first acoustic impedanceZ₁ substantially mismatched to the acoustic impedance of air Z_(A). Asecond reflective-region of the pair of regions has a second acousticimpedance Z₂ substantially dissimilar from the first acoustic impedance.In this embodiment, Z₁<Z₂.

FIG. 4B illustrates a cross-sectional view of another alternativeembodiment of the device 101 of FIG. 2. In the alternative embodiment,the layer of the first material 110 is shaped and configured to reflecta substantial portion of a specified incident air blast wave energy197-I and has a layer thickness 116 less than about 3 mm. The layer ofthe first material includes at least three reflective-regions. A firstreflective-region 110A of the at least three reflective-regions has afirst acoustic impedance Z₁ substantially mismatched to the acousticimpedance of air Z_(A). A second reflective-region of the at least threereflective-regions has a second acoustic impedance Z₂ substantiallydissimilar from the first acoustic impedance. A third reflective-regionof the at least three reflective-regions has a third acoustic impedanceZ₃. For example, in an embodiment, the specified incident air blast waveenergy arrives firstly at the first reflective region, arrives secondlyat the second reflective region, and arrives thirdly at the thirdreflective region. In an alternative embodiment that is not illustrated,the at least three reflective regions 110A, 110B, and 110C may bepositioned side-by-side with each occupying the full thickness 116 ofthe layer of first material and oriented to present the at least threeregions in parallel to the specified incident air blast wave energy197-I rather than in series as illustrated in FIG. 4B. In thisalternative embodiment, the specified incident air blast wave energyarrives substantially simultaneously at the first reflective region, thesecond acoustic region, and the third reflective region. In thisalternative embodiment, multiple instances of the at least threereflective regions 110A, 110B, and 110C may comprise the layer of thefirst material. In an embodiment, the layer of the first material isshaped and configured to reflect a substantial portion of a specifiedincident air blast wave energy and has a layer thickness less than about3 mm. The layer of the first material includes at least threereflective-regions. A first reflective-region of the at least threereflective-regions has a first acoustic impedance substantially Z₁mismatched to the acoustic impedance of air Z_(A). A secondreflective-region of the at least three reflective-regions has a secondacoustic impedance Z₂ substantially dissimilar from the first acousticimpedance. A third reflective-region of the at least threereflective-regions has a third acoustic impedance Z₃ substantiallydissimilar from the first acoustic impedance Z₁. In an embodiment, thelayer of the first material is shaped and configured to reflect asubstantial portion of a specified incident air blast wave energy andhas a layer thickness less than about 3 mm. The layer of the firstmaterial includes at least three reflective-regions. A firstreflective-region of the at least three reflective-regions has a firstacoustic impedance substantially Z₁ mismatched to the acoustic impedanceof air Z_(A). A second reflective-region of the at least threereflective-regions has a second acoustic impedance Z₂ substantiallydissimilar from the first acoustic impedance. A third reflective-regionof the at least three reflective-regions has a third acoustic impedanceZ₃ substantially dissimilar from the second acoustic impedance Z₂. In anembodiment, the layer of the first material is shaped and configured toreflect a substantial portion of a specified incident air blast waveenergy and has a layer thickness less than about 3 mm. The layer of thefirst material includes at least three reflective-regions. A firstreflective-region of the at least three reflective-regions has a firstacoustic impedance substantially Z₁ mismatched to the acoustic impedanceof air Z_(A). A second reflective-region of the at least threereflective-regions has a second acoustic impedance Z₂ substantiallydissimilar from the first acoustic impedance. A third reflective-regionof the at least three reflective-regions has a third acoustic impedanceZ₃ substantially dissimilar from the second acoustic impedance Z₂. Inthis embodiment, Z₁>Z₂. In an embodiment, the layer of the firstmaterial is shaped and configured to reflect a substantial portion of aspecified incident air blast wave energy and has a layer thickness lessthan about 3 mm. The layer of the first material includes at least threereflective-regions. A first reflective-region of the at least threereflective-regions has a first acoustic impedance substantially Z₁mismatched to the acoustic impedance of air Z_(A). A secondreflective-region of the at least three reflective-regions has a secondacoustic impedance Z₂ substantially dissimilar from the first acousticimpedance. A third reflective-region of the at least threereflective-regions has a third acoustic impedance Z₃ substantiallydissimilar from the second acoustic impedance Z₂. In this embodiment,Z₁<Z₂.

In an embodiment that is not illustrated, the layer of the firstmaterial 110 is shaped and configured to reflect a substantial portionof a specified incident air blast wave energy 197-I and has a layerthickness less than about 3 mm. The layer of the first material includesat least four reflective-regions. A first reflective-region of the atleast four reflective-regions has a first acoustic impedancesubstantially Z₁ mismatched to the acoustic impedance of air. A secondreflective-region of the at least four reflective-regions has a secondacoustic impedance Z₂. A third reflective-region of the at least fourreflective-regions has a third acoustic impedance Z₃. A fourthreflective-region of the at least four reflective-regions has a fourthacoustic impedance Z₄. In this embodiment, Z₃/Z₄ at least approximatelyequals Z₁/Z₂. In an embodiment of this embodiment, the specifiedincident air blast wave energy arrives firstly at the first reflectiveregion, arrives secondly at the second reflective region, arrivesthirdly at the third reflective region, and arrives fourthly at thefourth reflective region. In an alternative embodiment that also is notillustrated, the at least four reflective regions may be positionedside-by-side with each occupying the full thickness 116 of the layer offirst material and oriented to present the at least four regions inparallel to the specified incident air blast wave energy 197-I ratherthan in series as illustrated in FIG. 4B. In an embodiment of thisembodiment, the specified incident air blast wave energy arrivessubstantially simultaneously at the first reflective region, the secondreflective region, the third reflective region, and the fourthreflective region. In this alternative embodiment, multiple instances ofthe at least three reflective regions may comprise the layer of thefirst material.

Returning to FIG. 2, in an embodiment, the layer of the second material120 includes a layer of a second material shaped and configured toattenuate and to substantially increase a duration of the region ofoverpressure 24 of FIG. 1 of the specified incident air blast waveenergy transmitted 197-T through the layer of the first materialutilizing an inelastic response. The layer of the second material isshaped and configured for wearing proximate to the exterior portion 106of the human body 105. In some instances, substantially increasing aduration of the region of overpressure of the specified incident airblast wave energy may be implemented using voids, or inclusions such asmicrospheres or macrospheres in the second material. It is expected thatsubstantially increasing the duration of the specified incident airblast wave energy will decrease incoming incident air blast wave energyper unit of time, and thus provide a human protective response. In anembodiment, the layer of the second material includes a layer of asecond material shaped and configured to attenuate a substantial portionof the specified incident air blast wave energy transmitted through thelayer of the first material and to substantially decrease a slope of theshock front of the specified incident air blast wave energy transmittedthrough the layer of the first material utilizing an inelastic response.The layer of the second material is shaped and configured for wearingproximate to the exterior portion of the human body. In some instances,substantially decreasing the slope of the shock front 22 of FIG. 1 ofthe specified incident air blast wave energy may be implemented usingvoids, microspheres, or macrospheres in the second material. It isexpected that decreasing the slope of the shock front will provide ahuman protective response. In an embodiment, the layer of the secondmaterial includes a layer of a second material shaped and configured toattenuate a substantial portion of the specified incident air blast waveenergy transmitted through the layer of the first material and to widenthe leading edge of the shock front of the specified incident air blastwave energy transmitted through the layer of the first materialutilizing an inelastic response. The layer of the second material isshaped and configured for wearing proximate to the exterior portion ofthe human body. In an embodiment, the layer of the second materialincludes a layer of a second material shaped and configured to attenuatea substantial portion of the specified incident air blast wave energytransmitted through the layer of the first material and to shift thespectral peak of the specified incident air blast wave energytransmitted through the layer of the first material by about at leastone order-of-magnitude lower utilizing an inelastic response. The layerof the second material is shaped and configured for wearing proximate tothe exterior portion of the human body.

In an embodiment, the layer of the second material 120 includes a layerof a second material shaped and configured to attenuate a substantialportion of the specified incident air blast wave energy transmitted197-T through the layer of the first material 110 utilizing an inelasticresponse. The layer of the second material is shaped and configured forwearing proximate to the exterior portion 106 of the human body 105, andhas a layer thickness 126 of less than about 5 cm. In an embodiment, thelayer of the second material includes a layer of a second materialshaped and configured to attenuate a substantial portion of thespecified incident air blast wave energy transmitted through the layerof the first material utilizing an inelastic response. The layer of thesecond material is shaped and configured for wearing proximate to theexterior portion of the human body, and has a layer thickness of lessthan about 1 cm.

In an embodiment, the layer of the second material 120 includes a layerof a second material shaped and configured to attenuate a substantialportion of the specified incident air blast wave energy transmitted197-T through the layer of the first material 110 by at least 3 dButilizing an inelastic response. The layer of the second material isshaped and configured for wearing proximate to the exterior portion 106of the human body 105. The at least 3 db attenuation is expected toattenuate at least 50% of the specified incident air blast wave energytransmitted through the layer of the first material. In an embodiment,the layer of the second material includes a layer of a second materialshaped and configured to attenuate a substantial portion of thespecified incident air blast wave energy transmitted through the layerof the first material by at least 6 dB utilizing an inelastic response.The layer of the second material is shaped and configured. The at least6 db attenuation is expected to attenuate at least 75% of the specifiedincident air blast wave energy transmitted through the layer of thefirst material. In an embodiment, the layer of the second materialincludes a layer of a second material shaped and configured to attenuatea substantial portion of the specified incident air blast wave energytransmitted through the layer of the first material by at least 10 dButilizing an inelastic response. The layer of the second material isshaped and configured. The at least 10 db attenuation is expected toattenuate at least 90% of the specified incident air blast wave energytransmitted through the layer of the first material. In an embodiment,the layer of the second material includes a layer of a second materialshaped and configured to attenuate a substantial portion of thespecified incident air blast wave energy transmitted through the layerof the first material by at least 20 dB utilizing an inelastic response.The layer of the second material is shaped and configured. The at least20 db attenuation is expected to attenuate at least 99% of the specifiedincident air blast wave energy transmitted through the layer of thefirst material. In an embodiment, the layer of the second materialincludes a layer of a second material shaped and configured to attenuatea substantial portion of the specified incident air blast wave energytransmitted through the layer of the first material by at least 30 dButilizing an inelastic response. The layer of the second material isshaped and configured. The at least 30 db attenuation is expected toattenuate at least 99.9% of the specified incident air blast wave energytransmitted through the layer of the first material.

In an embodiment, the layer of the second material 120 includes a layerof an acoustic absorption material shaped and configured to attenuate asubstantial portion of the specified incident air blast wave energytransmitted 197-T through the layer of the first material 110 utilizingan inelastic response. The layer of the second material is shaped andconfigured for wearing proximate to the exterior portion 106 of thehuman body 105. In an embodiment, the layer of the second materialincludes a layer of a second material shaped and configured to absorb asubstantial portion of the specified incident air blast wave energytransmitted through the layer of the first material utilizing aninelastic response. The layer of the second material is shaped andconfigured for wearing proximate to the exterior portion of the humanbody.

In an embodiment, the layer of the second material 120 includes a layerof a second material shaped and configured to attenuate a substantialportion of the specified incident air blast wave energy transmitted197-T through the layer of the first material 110 utilizing an inelasticresponse. The layer of the second material is shaped and configured forwearing proximate to the exterior portion 106 of the human body 105. Theinelastic response of the layer of the second material is selected as atleast substantially likely to provide a human-protective response to thespecified incident air blast wave energy transmitted through the layerof the first material. In an embodiment, the layer of the secondmaterial includes a layer of a second material shaped and configured toattenuate a substantial portion of the specified incident air blast waveenergy transmitted through the layer of the first material utilizing aninelastic response. The layer of the second material is shaped andconfigured for wearing proximate to the exterior portion of the humanbody. The inelastic response of the second material includes aninelastic crush response to the specified incident air blast wave energytransmitted through the layer of the first material. For example, aninelastic crush response may be illustrated by the crush plateau zone200 or region of FIG. 3.

Continuing with reference to FIG. 2, in an embodiment, the layer of thesecond material 120 is shaped and configured to attenuate a substantialportion of the specified incident air blast wave energy transmitted197-T through the layer of the first material 110 utilizing an inelasticresponse. The layer of the second material shaped and configured forwearing proximate to the exterior portion 106 of the human body 105. Theinelastic response of the second material includes an inelastic crushresponse to the specified incident air blast wave energy transmittedthrough the layer of the first material at an overpressure greater thanabout 0.1 bar. In an embodiment, the layer of the second material isshaped and configured to attenuate a substantial portion of thespecified incident air blast wave energy transmitted through the layerof the first material utilizing an inelastic response. The layer of thesecond material is shaped and configured for wearing proximate to theexterior portion of the human body. The inelastic response of the secondmaterial includes an inelastic crush response to the specified incidentair blast wave energy transmitted through the layer of the firstmaterial at an overpressure greater than about 1 bar. In an embodiment,the layer of the second material is shaped and configured to attenuate asubstantial portion of the specified incident air blast wave energytransmitted through the layer of the first material utilizing aninelastic response. The layer of the second material is shaped andconfigured for wearing proximate to the exterior portion of the humanbody. The inelastic response of the second material includes aninelastic crush response to the specified incident air blast wave energytransmitted through the layer of the first material at an overpressuregreater than about 3 bar. In an embodiment, the layer of the secondmaterial is shaped and configured to attenuate a substantial portion ofthe specified incident air blast wave energy transmitted through thelayer of the first material utilizing an inelastic response. The layerof the second material is shaped and configured for wearing proximate tothe exterior portion of the human body. The inelastic response of thesecond material includes an inelastic crush response to the specifiedincident air blast wave energy transmitted through the layer of thefirst material at an overpressure greater than about 6 bar. In anembodiment, the layer of the second material is shaped and configured toattenuate a substantial portion of the specified incident air blast waveenergy transmitted through the layer of the first material utilizing aninelastic response. The layer of the second material is shaped andconfigured for wearing proximate to the exterior portion of the humanbody. The inelastic response of the second material includes aninelastic crush response to the specified incident air blast wave energytransmitted through the layer of the first material at an overpressuregreater than about 10 bar.

In an embodiment, the layer of the second material 120 includes a layerof a metallic foam material shaped and configured to attenuate asubstantial portion of the specified incident air blast wave energytransmitted 197-T through the layer of the first material 110 utilizingan inelastic response. The layer of the second material is shaped andconfigured for wearing proximate to the exterior portion 106 of thehuman body 105. For example, the metallic foam may include an aluminumfoam. For example, the metallic foam may include a closed cell metallicfoam. For example, the metallic foam may include open cell metallicfoam. For example the metallic foam may include a sandwich of at leasttwo metallic foams.

In an embodiment, the second material 120 includes a layer of an aerogelmaterial shaped and configured to attenuate a substantial portion of thespecified incident air blast wave energy transmitted 197-T through thelayer of the first material 110 utilizing an inelastic response. Thelayer of the second material is shaped and configured for wearingproximate to the exterior portion of the human body. In an embodiment,the second material includes a layer of a syntactic foam material shapedand configured to attenuate a substantial portion of the specifiedincident air blast wave energy transmitted through the layer of thefirst material utilizing an inelastic response. The layer of the secondmaterial is shaped and configured for wearing proximate to the exteriorportion of the human body.

In an embodiment, the second material 120 includes a layer of a plasticfoam material shaped and configured to attenuate a substantial portionof the specified incident air blast wave energy transmitted 197-Tthrough the layer of the first material 110 utilizing an inelasticresponse. The layer of the second material is shaped and configured forwearing proximate to the exterior portion of the human body. Forexample, the layer of the plastic foam material may include a hybridcomposite of phenolic foams reinforced with chopped glass and aramidfibers in varied proportions.

In an embodiment, the second material 120 includes a layer of a periodiccellular metal material shaped and configured to attenuate a substantialportion of the specified incident air blast wave energy transmitted197-T through the layer of the first material 110 utilizing an inelasticresponse. The layer of the second material is shaped and configured forwearing proximate to the exterior portion of the human body. Forexample, a layer of a periodic cellular metal may include less thanabout 20% interior volume occupied by metal. For example, the layer of aperiodic cellular metal may include closed cell honeycomb, prismaticcorrugations, or lattice structures with hollow trusses and cell sizesthe millimeter range.

In an embodiment, the layer of the second material 120 is shaped andconfigured to attenuate a substantial portion of the specified incidentair blast wave energy transmitted 197-T through the layer of the firstmaterial 110 utilizing a high-modulus low-density second material in aninelastic response. For example, a high-modulus low-density material mayinclude a material like a syntactic foam that includes microspheres orhollow microballoons. For example, a high-modulus low-density materialmay include a material like Corecell™ S-Foam manufactured by SP-HighModulus/Gurit of Isle of Wright, UK. The layer of the second material isshaped and configured for wearing proximate to the exterior portion ofthe human body. In an embodiment, the second material includes a layerof a high-modulus low-density second material shaped and configured toattenuate a substantial portion of the specified incident air blast waveenergy transmitted through the layer of the first material utilizing aninelastic response. The layer of the second material is shaped andconfigured for wearing proximate to the exterior portion of the humanbody.

In an embodiment, the layer of the second material 120 is shaped andconfigured to attenuate a substantial portion of the specified incidentair blast wave energy transmitted 197-T through the layer of the firstmaterial 110 utilizing an inelastic response. The layer of the secondmaterial is shaped and configured for wearing proximate to the exteriorportion of the human body. The layer of the second material has a massper unit area less than about 1 g/cm². In an embodiment, the layer ofthe second material 120 is shaped and configured to attenuate asubstantial portion of the specified incident air blast wave energytransmitted 197-T through the layer of the first material 110 utilizingan inelastic response. The layer of the second material is shaped andconfigured for wearing proximate to the exterior portion of the humanbody. The layer of the second material has a mass per unit area lessthan about 0.3 g/cm². In an embodiment, the layer of the second material120 is shaped and configured to attenuate a substantial portion of thespecified incident air blast wave energy transmitted 197-T through thelayer of the first material 110 utilizing an inelastic response. Thelayer of the second material is shaped and configured for wearingproximate to the exterior portion of the human body. The layer of thesecond material has a mass per unit area less than about 0.1 g/cm².

In an embodiment, the layer of the second material 120 is shaped andconfigured to attenuate a substantial portion of the specified incidentair blast wave energy transmitted 197-T through the layer of the firstmaterial 110 utilizing an inelastic response. The layer of the secondmaterial has a shape configured for wearing proximate to the exteriorportion 106 of the human body 105. In an embodiment, the layer of thesecond material is shaped and configured to attenuate a substantialportion of the specified incident air blast wave energy transmittedthrough the layer of the first material utilizing an inelastic response.The layer of the second material has a shape configured for wearingproximate to a portion of a human head (not illustrated). For example,the layer of the second material may be contoured to closely fit theportion of a human head and to minimize or eliminate the air gap 198. Inan embodiment, the layer of the second material is shaped and configuredto attenuate a substantial portion of the specified incident air blastwave energy transmitted through the layer of the first materialutilizing an inelastic response. The layer of the second material isshaped and configured to fit in close proximity to the exterior portionof the human body. For example, the close proximity may include touchingthe exterior portion of the human body. In an embodiment, the layer ofthe second material is shaped and configured to attenuate a substantialportion of the specified incident air blast wave energy transmittedthrough the layer of the first material utilizing an inelastic response.The layer of the second material has a shape configured to fit againstthe exterior portion of the human body.

In an embodiment, the layer of the second material 120 is shaped andconfigured to attenuate a substantial portion of the specified incidentair blast wave energy transmitted 197-T through the layer of the firstmaterial 110 utilizing a single-use inelastic response. The layer of thesecond material is shaped and configured for wearing proximate to theexterior portion 106 of the human body 105.

In an embodiment, the device 101 includes a label (not illustrated)indicating use of the device is limited to a single exposure to an airblast wave energy, such as the selected incident air blast wave energy197-I. In an embodiment, the device includes an indicator 191 configuredto provide a human-perceivable indication that the device has beenexposed to an air blast wave energy, such as the selected incident airblast wave energy. For example, the indicator may be implemented usingpores or small spheres filed with a colored liquid that bleed into avisible region of the device when crushed by the incident air blast waveenergy. An example indicator using a color changing crystal may be foundin D. K. Cullen, et al., Color changing photonic crystals detect blastexposure, Science 19 Nov. 2010: Vol. 330 no. 6007 p. 1023.

FIGS. 5 and 6 illustrate cross-sectional views of alternativeembodiments of the device 101 of FIG. 2. The device includes a spallliner 140 shaped and configured to restrain at least one fragment brokenfrom of the layer of the first material 110 by the specified incidentair blast wave energy 197-I. For example, the spall liner may be madeusing aramid fibers, such as KEVLAR®, or TWARON®. For example, the spallliner may be made using polyethylene fibers, such as DYNEEMA®, orZYLON®. For example, the spall liner may be made using a very hightensile strength biomaterial, such as spider silk, spider silk fromgoat's milk, or similar materials. For example, the spall liner may bemade using polyethylene, polypropylene, composite laminate, E-glass, orand S2-glass materials. FIG. 5 illustrates an alternative embodimentwhere the spall liner is interposed between the layer of the firstmaterial 110 and the layer of the second material. The layer of thefirst material includes the front surface 112 and the back surface 114,the layer of the second material includes the front surface 122 and theback surface 124, the spall liner includes a front surface 142 and aback surface 144. In this embodiment, at least a portion of the backsurface of the layer of the first material is proximate 146 to at leasta portion of the front surface of the spall liner, and at least aportion of the back surface of the spall liner is proximate to the frontsurface of the layer of the second material. For example, two materialsthat are proximate may include two materials that are in physicalcontact, joined, bonded, fused, or coupled. For example, two materialsthat are proximate may include two materials that are joined by anadhesive, such as contact cement, film, adhesive, wax, or resin. Forexample, two materials that are proximate may include two materials thatare joined by a thermal fusion.

FIG. 6 illustrates an alternative embodiment where the spall liner 140is interior of the layer of the second material 120. In this embodiment,at least a portion of the back surface 124 (not illustrated) of thelayer of the first material 110 (not illustrated) is proximate 180 (notillustrated) to at least a portion of the front surface 122 of the layerof the second material, and at least a portion of the back surface 124of the layer of the second material is proximate 146 to at least aportion of the front surface 142 of the spall liner.

Returning to FIG. 2, in an embodiment the layer of the first material110 includes a front surface 112 and a back surface 114, and the layerof the second material 120 includes a front surface 122 and a backsurface 124. At least a portion of the back surface of the layer of thefirst material is joined proximate 180 to the at least a portion of thefront surface of the layer of the second material. In an embodiment, theat least a portion of the back surface of the layer of the firstmaterial is joined at the proximity of the at least a portion of thefront surface of the layer of the second material. The joined firstmaterial and the second material forming an at least substantially stiffassembly. For example, the joined first material and the second materialmay have a specific bending stiffness in the range of an aluminum foamsandwich, which may be approximately 41.5 [10⁴N mm³/kG]. In anembodiment, the at least a portion of the back surface of the layer ofthe first material is joined at the proximity of the at least a portionof the front surface of the layer of the second material. The joinedfirst material and the second material forming an at least substantiallyflexible assembly. For example, the joined first material and the secondmaterial may have a specific bending stiffness in the range of aluminum,which may be approximately 2.5[10⁴ N mm³/kG]. In an embodiment, the atleast a portion of the back surface of the layer of the first materialis acoustically coupled at the proximity of the at least a portion ofthe front surface of the layer of the second material. In an embodiment,the at least a portion of the back surface of the layer of the firstmaterial is proximate to at least a portion of the front surface of thelayer of the second material. The proximate first material and thesecond material are shaped and configured such that the device iswearable proximate to the exterior portion 106 of the human body 105without a significant continuous air path between a portion of the frontsurface 112 of the first material and at least one portion of theexterior portion of the human body.

FIG. 7 illustrates a cross-sectional view of an alternative embodimentof the device 101 of FIG. 2. In an embodiment, the device includes alayer of a ballistic material 170 shaped and configured to substantiallyattenuate energy of an object (not illustrated) impacting the (hereafter“impacting object”) exterior portion 106 of the human body 105. Forexample, an impacting object may include a ballistic, projectile, bluntforce, or shrapnel. For example, the energy of an impacting object mayinclude a kinetic energy of the impacting object. For example, theenergy of an impacting object may include a rotational or spinningenergy, such as a rotating, tumbling, or spinning of a projectile. Thelayer of the first material 110 includes a front surface 112 and a backsurface 114, the layer of the second material 120 includes a frontsurface 122 and a back surface 124, and the layer of the ballisticmaterial 170 includes a front surface 172 and a back surface 174. In anembodiment, the front surface of the layer of ballistic material may beconsidered an exterior or outside surface of a helmet. In an embodiment,the back surface may be considered an interior or inside surface of ahelmet. In an embodiment, at least a portion of the back surface of thelayer of the ballistic material is proximate to the front surface of thelayer of the first material, and at least a portion of the back surfaceof the layer of the first material is proximate to at least a portion ofthe front surface of the layer of the second material. In an embodiment,at least a portion of the back surface of the layer of the ballisticmaterial is joined to the front surface of the layer of the firstmaterial, and at least a portion of the back surface of the layer of thefirst material is joined to at least a portion of the front surface ofthe layer of the second material. In an embodiment, at least a portionof the back surface of the layer of the ballistic material isacoustically coupled to the front surface of the layer of the firstmaterial, and at least a portion of the back surface of the layer of thefirst material is acoustically coupled to at least a portion of thefront surface of the layer of the second material. In an embodiment (notillustrated), at least a portion of the back surface of the layer of thefirst material is proximate to the front surface of the layer of theballistic material, and at least a portion of the back surface of thelayer of the ballistic material proximate to at least a portion of thefront surface of the layer of the second material. In an embodiment (notillustrated), at least a portion of the back surface of the layer of thefirst material is proximate to the front surface of the layer of thesecond material, and at least a portion of the back surface of the layerof the second material is proximate to at least a portion of the frontsurface of the layer of the ballistic material.

Returning to FIG. 2, in an embodiment, the device 101 further comprisesa retaining apparatus (not illustrated) configured to hold the layer ofthe first material 110 and the layer of the second material 120 adjacentto the exterior portion 106 of the human body 105. In an embodiment, theretaining apparatus includes at least one strap. For example, theretaining apparatus may include a chin strap. For example, the retainingapparatus may include a removable fixation device. For example, theretaining apparatus is configured to hold the layer of the firstmaterial and the layer of the second material in a substantially directcontact with or adjacent to the exterior portion of the human body. Insuch an example, the air gap 198 is minimized or non-existent. In anembodiment, the retaining apparatus in cooperation with the layer of thesecond material are configured to hold the layer of the second materialimmediately against the exterior portion of the human body. In such anembodiment, the air gap 198 is minimized or non-existent.

Continuing with FIG. 2, in an embodiment, the device 101 includes thelayer of a first material 110. The layer of first material is shaped andconfigured to reflect at least 50% of the shock front 22 of a specifiedincident air blast wave energy 197-I. The first material has an acousticimpedance substantially mismatched to the acoustic impedance of air, anda layer thickness 116 of less than about 3 mm. The device includes thelayer of the second material 120. The layer of the second material isshaped and configured to attenuate a substantial portion of thespecified incident air blast wave energy transmitted 197-T through thelayer of the first material utilizing an inelastic response. The layerof the first material includes a front surface and a back surface, andthe layer of the second material includes a front surface and a backsurface. At least a portion of the back surface of the layer of thefirst material is proximate to at least a portion of the front surfaceof the layer of the second material.

Continuing with FIG. 2, in an embodiment, the device 101 includes thelayer of a first material 110. The layer of first material is shaped andconfigured to reflect at least 10% of the shock front 22 of a specifiedincident air blast wave energy 197-I. The first material has an acousticimpedance substantially mismatched to the acoustic impedance of air, anda layer thickness less than about 3 mm. The device includes the layer ofthe second material 120. The layer of a second material is shaped andconfigured to attenuate a substantial portion of the specified incidentair blast wave energy transmitted 197-T through the layer of the firstmaterial utilizing an inelastic response The layer of the first materialincludes a front surface and a back surface, and the layer of the secondmaterial includes a front surface and a back surface. At least a portionof the back surface of the layer of the first material is proximate toat least a portion of the front surface of the layer of the secondmaterial.

FIG. 8 illustrates an example operational flow 300 in which embodimentsof designing a wearable air blast wave energy protection device may beimplemented. After a start operation, the operational flow includes areflection modeling operation 310. The reflection modeling operationincludes computer modeling at least two candidate reflective materialsfor a first human-protective and primarily reflective response to aspecified incident air blast wave energy. The computer modeling of theat least two candidate reflective materials is at least partially basedon respective acoustic impedances of the at least two candidatereflective materials to the specified incident air blast wave energy.The air blast wave energy includes an air blast wave energy produced bya high intensity explosive. In an embodiment, the blast event 193creates the air blast wave 195, a portion of which proceeds toward thehuman body 105 as depicted by the incident air blast wave energy 197-Idescribed in conjunction with FIG. 2. The respective acoustic impedancesof the at least two candidate reflective materials are eachsubstantially mismatched to the acoustic impedance of air. Theoperational flow includes a reflective material selecting operation 320.The reflective material selecting operation includes selecting a layerof a first material from the at least two candidate reflectivematerials. The selecting is based at least partially on the computermodeling of the at least two possible layers of reflective material. Inan embodiment, the selected layer of the first material includesselecting the layer of the first material 110 described in conjunctionwith FIG. 2. The operational flow includes an attenuation modelingoperation 330. The attenuation modeling operation includes computermodeling at least two candidate attenuative materials for a secondhuman-protective and primarily attenuative response to the specifiedincident air blast wave energy transmitted through the selected layer ofthe first material. The computer modeling of the at least two candidateattenuative materials is at least partially based on respectiveinelastic responses of the two candidate attenuative materials to thespecified incident air blast wave energy transmitted through theselected layer of the first material. In an embodiment, the specifiedincident air blast wave energy transmitted through the layer of thefirst material includes the specified incident air blast wave energytransmitted 197-T through the layer of the first material described inconjunction with FIG. 2. The operational flow includes an attenuationmaterial selecting operation 360. The attenuation material selectingoperation includes selecting a layer of a second material from at leasttwo candidate attenuative materials. The selecting is based at leastpartially on the computer modeling of at least two candidate attenuativematerials. For example, the selected layer of the second material mayinclude the layer of the second material 120 described in conjunctionwith FIG. 2. The operational flow includes storage operation 380. Thestorage operation includes electronically maintaining informational datacorresponding to the selected layer of the first material and theselected layer of the second material. The operational flow includes anend operation.

As used herein for example, “selecting” or “selected” may include anyprocess or methodology used to identify or select for use one or morematerials, or a parameter of one or more materials from a plurality ofcandidates. As used herein for example, “selecting” or “selected” mayinclude any process or methodology used to identify or choose anacoustic reflection, an acoustic impedance, an acoustic attenuation, ora layer thickness parameter of one or more materials. As used herein forexample, “selecting” or “selected” may include any process ormethodology used to identify or choose one or more materials having aparticular acoustic reflection, acoustic impedance, acousticattenuation, or layer thickness parameter. As used herein for example, aprocess to implement a “selecting” or “selected” may include, but is notlimited to, a user based selecting, user identified selecting, softwareanalysis based selecting, algorithm based selecting, computer mediatedselecting, operations research based selection, optimization basedselecting, simulation based selecting, queuing theory based selecting,and/or game theory based selecting.

FIG. 9 illustrates alternative embodiments of the reflection modelingoperation 310 of the operational flow 300 of FIG. 8. The reflectionmodeling operation may include at least one alternative embodiment. Theat least one alternative embodiment may include an operation 312 or anoperation 314. The operation 312 includes computer modeling at least twocandidate reflective materials for a first advantageous human-protectiveand primarily reflective response to a specified incident air blast waveenergy. The computer modeling of the at least two candidate reflectivematerials is at least partially based on respective acoustic impedancesof the at least two candidate reflective materials to the specifiedincident air blast wave energy. The respective acoustic impedances ofthe at least two candidate reflective materials are each substantiallymismatched to the acoustic impedance of air. For example, anadvantageous response may include a response likely to provide asignificant measure of human protection in a combat condition. Forexample, an advantageous response may include a response likely to aidin providing human protection to the specified incident air blast waveenergy. For example, an advantageous response may include a responselikely to provide a more suitable protection to the specified incidentair blast wave energy than another candidate material. In an embodiment,the computer modeling at least two candidate reflective materialsincludes computer modeling at least two combat-conditions appropriatecandidate reflective materials for human-protective and primarilyreflective response. For example, a combat conditions-appropriatecandidate reflective material for a human-protective and primarilyreflective response may include candidate reflective material having aweight or configuration that a soldier is reasonably likely to wear incombat conditions. In an embodiment, the computer modeling at least twocandidate reflective materials includes computer modeling at least twocandidate reflective materials for a combat-conditions optimizedcandidate reflective materials for a human-protective and primarilyreflective response. For example, the combat-conditions optimizedcandidate reflective materials for human-protective and primarilyreflective response may include candidate reflective materialsreasonably attainable within weight, environment, or budgetaryrestrictions imposed on combat equipment.

The operation 314 includes computer modeling at least two candidatereflective materials for a first human-protective and primarilyreflective response to a specified incident air blast wave energy. Thecomputer modeling of the at least two candidate reflective materials isat least partially based on (i) respective acoustic impedances of the atleast two candidate reflective materials to the specified incident airblast wave energy and (ii) a layer thickness of less than about 3 mm.The respective acoustic impedances of the at least two candidatereflective materials are each substantially mismatched to the acousticimpedance of air.

FIG. 10 illustrates alternative embodiments of the reflective materialselecting operation 320 of the operational flow 300 of FIG. 8. Thereflective material selecting operation may include at least onealternative embodiment, such as an operation 322. The operation 322includes selecting a layer of a first material from the at least twocandidate reflective materials. The selecting based at least partiallyon the computer modeling of the at least two possible layers ofreflective material and on providing an advantageous firsthuman-protective and substantial reflective response to a specifiedincident air blast wave energy. In an embodiment, the selecting a layerof a first material includes selecting a layer of a first materialproviding a combat-situation appropriate first human-protective andsubstantial reflective response to a specified incident air blast waveenergy. In an embodiment, the selecting a layer of a first materialincludes selecting a layer of a first material providing acombat-conditions optimized first human-protective and substantialreflective response to a specified incident air blast wave energy.

FIG. 11 illustrates alternative embodiments of the attenuation modelingoperation 330 of the operational flow 300 of FIG. 8. The attenuationmodeling operation may include at least one alternative embodiment. Theat least one alternative embodiment may include an operation 332, anoperation 334, an operation 336, or an operation 338. The operation 332includes computer modeling at least two candidate attenuative materialsfor a second advantageous human-protective and primarily attenuativeresponse to the specified incident air blast wave energy transmittedthrough the selected layer of first material. The computer modeling ofthe at least two candidate attenuative materials is at least partiallybased on respective inelastic responses of the two candidate attenuativematerials to the specified incident air blast wave energy transmittedthrough the selected layer of the first material. For example, thecomputer modeling at least two candidate attenuative materials for asecond advantageous human-protective and primarily attenuative responsemay include computer modeling at least two candidate attenuativematerials having a combat-conditions appropriate human-protective andprimarily attenuative response to the specified incident air blast waveenergy transmitted through the selected layer of first material. Forexample, combat conditions-appropriate candidate attenuative materialsfor a human-protective and primarily attenuative response may includecandidate attenuative materials having a weight or configuration that asoldier is reasonably likely to wear in a combat conditions. Forexample, the computer modeling at least two candidate attenuativematerials may include computer modeling at least two candidateattenuative materials for a combat-conditions optimized candidateattenuative materials for a human-protective and primarily attenuativeresponse. For example, the combat-conditions optimized candidateattenuative materials for human-protective and primarily attenuativeresponse may include candidate attenuative materials reasonablyattainable within weight, environment, or budgetary restrictions imposedon combat equipment.

The operation 334 includes computer modeling at least two candidateattenuative materials for a second human-protective and primarilyattenuative response to the specified incident air blast wave energytransmitted through the selected layer of the first material. Thecomputer modeling of the at least two candidate attenuative materials isat least partially based on (i) respective inelastic responses of thetwo candidate attenuative materials to the specified incident air blastwave energy transmitted through the selected layer of the first materialand (ii) a layer thickness of less than about 3 cm. The operation 336includes computer modeling at least two candidate attenuative materialsfor a second human-protective and primarily attenuative response to thespecified incident air blast wave energy transmitted through theselected layer of the first material. The computer modeling of the atleast two candidate attenuative materials is at least partially based on(i) respective inelastic responses of the two candidate attenuativematerials to the specified incident air blast wave energy transmittedthrough the layer of the selected layer of the first material and (ii) alayer thickness of less than about 2 cm. The operation 338 includescomputer modeling at least two candidate attenuative materials for asecond human-protective and primarily attenuative response to thespecified incident air blast wave energy transmitted through theselected layer of the first material. The computer modeling of the atleast two candidate attenuative materials is at least partially based on(i) respective inelastic responses of the two candidate attenuativematerials to the specified incident air blast wave energy transmittedthrough the selected layer of the first material and (ii) a layerthickness of less than about 1 cm.

FIG. 12 illustrates alternative embodiments of the attenuation modelingoperation 330 of the operational flow 300 of FIG. 8. The attenuationmodeling operation may include at least one alternative embodiment. Theat least one alternative embodiment may include an operation 342, anoperation 344, an operation 346, or an operation 348. The operation 342includes computer modeling at least two candidate attenuative materialsfor a second human-protective and primarily attenuative response to thespecified incident air blast wave energy transmitted through theselected layer of the first material. The computer modeling of the atleast two candidate attenuative materials is at least partially based onacoustic absorption provided by respective inelastic responses of thetwo candidate attenuative materials to the specified incident air blastwave energy transmitted through the selected layer of the firstmaterial. The operation 344 includes computer modeling at least twocandidate attenuative materials for a second human-protective andprimarily attenuative response to the specified incident air blast waveenergy transmitted through the selected layer of the first material. Thecomputer modeling of the at least two candidate attenuative materials isat least partially based on respective inelastic crush responses of thetwo candidate attenuative materials to the specified incident air blastwave energy transmitted through the selected layer of the firstmaterial. The operation 346 includes computer modeling at least twocandidate attenuative materials for a second human-protective andprimarily attenuative response to the specified incident air blast waveenergy transmitted through the selected layer of the first material. Thecomputer modeling of the at least two candidate attenuative materials isat least partially based on respective inelastic crush responses of thetwo candidate attenuative materials to the specified incident air blastwave energy transmitted through the selected layer of the first materialat an overpressure greater than about 1 bar. The operation 348 includescomputer modeling at least two candidate attenuative materials for asecond human-protective and primarily attenuative response to thespecified incident air blast wave energy transmitted through theselected layer of the first material. The computer modeling of the atleast two candidate attenuative materials is at least partially based onrespective inelastic crush responses of the two candidate attenuativematerials to the specified incident air blast wave energy transmittedthrough the selected layer of the first material at an overpressuregreater than about 3 bar.

FIG. 13 illustrates alternative embodiments of the attenuation modelingoperation 330 of the operational flow 300 of FIG. 8. The attenuationmodeling operation may include at least one alternative embodiment. Theat least one alternative embodiment may include an operation 352, or anoperation 354. The operation 352 includes computer modeling at least twocandidate attenuative materials for a second human-protective andprimarily attenuative response to the specified incident air blast waveenergy transmitted through the selected layer of the first material. Thecomputer modeling of the at least two candidate attenuative materials isat least partially based on respective inelastic crush responses of thetwo candidate attenuative materials to the specified incident air blastwave energy transmitted through the selected layer of the first materialat an overpressure greater than about 6 bar. The operation 354 includescomputer modeling at least two candidate attenuative materials for asecond human-protective and primarily attenuative response to thespecified incident air blast wave energy transmitted through theselected layer of the first material. The computer modeling of the atleast two candidate attenuative materials is at least partially based onrespective inelastic crush responses of the two candidate attenuativematerials to the specified incident air blast wave energy transmittedthrough the selected layer of the first material at an overpressuregreater than about 10 bar.

FIG. 14 illustrates alternative embodiments of the attenuation materialselecting operation 360 of the operational flow 300 of FIG. 8. Theattenuation material selecting operation may include an operation 362.The operation 362 includes selecting a layer of a second material fromthe at least two candidate attenuative materials. The selecting based atleast partly on the computer modeling of the at least two layers ofattenuative material and on providing an advantageous secondhuman-protective and substantial attenuative response to the specifiedincident air blast wave energy transmitted through the selected layer ofthe first material. For example, the selecting a layer of a secondmaterial may include selecting a layer of a second material providing acombat-situation appropriate second human-protective and substantialattenuative response to the specified incident air blast wave energytransmitted through the selected layer of the first material. Forexample, the selecting a layer of a second material may includeselecting a layer of a second material providing a combat-conditionsoptimized second human-protective and substantial reflective response tothe specified incident air blast wave energy transmitted through theselected layer of the first material.

FIG. 15 illustrates alternative embodiments of operational flow 300 ofFIG. 8. The operational flow 306 may include at least one alternativeembodiment. The at least one alternative embodiment may include anoperation 370, an operation 374, or an operation 382. The operation 370includes computer modeling at least two candidate methods of joining thelayer of the first material and the layer of the second material. Thecomputer modeling is at least partially based on an attribute of (i) thespecified incident air blast wave energy, and an attribute of either(ii) the first material relative to the specified incident air blastwave energy or (iii) the second material relative to the specifiedincident air blast wave energy. For example, the computer modeling maybe at least partially based on at least one of a thickness, orientation,affixation, adhere, or acoustic parameter of a candidate method ofjoining. For example, the computer modeling may be at least partiallybased on at least one of an absence or presence of an acoustic joiningcompound or structure. For example, the computer modeling may be atleast partially based on at least one of a specific acoustic property ofa joining compound. In an embodiment, the operation 370 may include atleast one alternative embodiment, such as an operation 372. Theoperation 372 includes computer modeling at least two candidate methodsof joining for a third human-protective joining of the layer of thefirst material and the layer of the second material to the specifiedincident air blast wave energy. The computer modeling is at leastpartially based on an attribute of the first material, an attribute ofthe second material, or an attribute of the specified incident air blastwave energy.

The operation 374 includes selecting a method of joining in response tothe computer modeling of at least two candidate methods of joining. Inan embodiment, the operation 374 may include at least one alternativeembodiment, such as an operation 376. The operation 376 includesselecting a method of joining from the at least two candidate methods ofjoining in response to the computer modeling of the at least twocandidate methods of joining.

In an embodiment, the storage operation 380 may include at least onealternative embodiment, such as the operation 382. The operation 382includes electronically maintaining informational data corresponding tothe selected layer of the first material, the selected layer of thesecond material, and the selected method of joining.

FIG. 16 illustrates alternative embodiments of the storage operation 380of the operational flow 300 of FIG. 8. The storage operation may includean alternative embodiment, such as an operation 384. The operation 384includes electronically transmitting the informational data to a personor machine in a format suitable for use in manufacturing the wearableblast wave protection device. For example, the information data may betransmitted via email, a network, or the Internet.

FIG. 17 illustrates an example operational flow 400 in which embodimentsof Manufacturing a wearable air blast wave energy protection device maybe implemented. After a start operation, the operational flow includes areflective material receiving operation 410. The reflective materialreceiving operation includes receiving a layer of a first materialselected to provide a first reflective response to a specified incidentair blast wave energy. The layer of the first material was selected atleast partially based on a first acoustic impedance of the firstmaterial to the specified incident air blast wave energy, and on asubstantial mismatch between the first acoustic impedance and theacoustic impedance of air. In an embodiment, the layer of the firstmaterial was selected to provide a first advantageous human-protectiveand primarily reflective response to a specified incident air blast waveenergy. For example, the reflective material receiving operation mayinclude receiving the first layer of material 110 described inconjunction with FIG. 2.

An attenuative material receiving operation 420 includes receiving alayer of a second material selected to provide a second attenuativeresponse to the specified incident air blast wave energy transmittedthrough the first material. The layer of the second material selected atleast partially based on an inelastic response of the second material tothe specified incident air blast wave energy transmitted through thelayer of the first material. In an embodiment, the layer of the secondmaterial was selected to provide a second advantageous human-protectiveand primarily attenuative response to the specified incident air blastwave energy transmitted through the first material. For example, thesecond receiving operation may include receiving the second layer ofmaterial 120 described in conjunction with FIG. 2.

A joining operation 430 includes joining at least a portion of the firstmaterial and at least a portion of the second material. In anembodiment, the joining operation may include at least one alternativeembodiment, such as an operation 432. In the operation 432, the joiningis selected at least partially based on an attribute of the layer of thefirst material, an attribute of the layer of the second material, or anattribute of the specified incident air blast wave energy transmittedthrough the layer of the first material. For example, the joining of atleast a portion of the first material and at least a portion of thesecond material may include at least one of placing merely proximate,affixing, adhering, acoustically joining, acoustically coupling, oracoustically de-coupling the first material and the second material tothe specified incident air blast wave energy. For example, the joiningmay include a joining selected to provide a third advantageoushuman-protective and primarily acoustic interface between the firstmaterial and the second material to the specified incident air blastwave energy. In an embodiment, the joining includes joining to form theair blast wave energy protection device. The joining selected at leastpartially based on an attribute of the layer of the first material, anattribute of the layer of the second material, or an attribute of thespecified incident air blast wave energy transmitted through the layerof the first material. For example, the joining of at least a portion ofthe first material and at least a portion of the second material mayinclude placing the first material 110 and the second material 120proximate 180 as described in conjunction with FIG. 2.

FIG. 18 illustrates alternative embodiments of the operational flow 400of FIG. 17. The operational flow may include an alternative embodimentillustrated as an operation 480. The operation 480 may include at leastone of an operation 442, an operation 444, an operation 446, anoperation 448, or an operation 452. The operation 442 includes shapingthe layer of the second material into a configuration suitable forwearing proximate to the exterior portion of the human body. Theoperation 444 includes shaping the joined layer of the first materialand the layer of a second material into a layered physical formconfigured or user-configurable for wearing proximate to the exteriorportion of the human body. The operation 446 includes shaping the joinedlayer of the first material and the layer of the second material into aphysical form configured or user-configurable for wearing proximate tothe exterior portion of the human body with the second layer proximateto the exterior portion of the human body. In an embodiment, theoperation 446 includes shaping the joined layer of the first materialand the layer of the second material into a physical form configured oruser-configurable for wearing proximate to the exterior portion of thehuman body with the second layer proximate to the exterior portion ofthe human body with no substantial air gap 198 (the air gap isillustrated in FIG. 2). The operation 448 includes attaching at least aportion of the layer of the first material or the layer of the secondmaterial to a retaining strap. The retaining strap is configured toremovably secure the joined layer of the first material and layer of thesecond material proximate to the exterior portion of the human body. Inan embodiment, the retraining strap includes a chin strap. For example,the retaining strap may include a retaining strap configured in a mannersimilar to retaining straps on the U.S. Military's Advanced CombatHelmet (ACH) presently used in the wars in Iraq or Afghanistan. SeeTechnical Manual Operator's Manual for Advanced Combat Helmet (ACH),0002-3, Dept. of the Army (TM 10-8470-204-14 Mar. 2008). In anembodiment, the retraining strap includes a retaining strap attached toa ballistic helmet, and at least a portion of the ballistic helmet iscoupled to the layer of the first material or the layer of the secondmaterial. The operation 452 includes attaching the joined layer of thefirst material and the layer of the second material to a carrier shapedand configured to be secured proximate to the exterior portion of thehuman body. In an embodiment, the carrier is also shaped and configuredto provide a protection against impacting objects. In an embodiment, thecarrier is also shaped and configured to maintain a physical integrityof the coupled first material and second material before receiving aninstance of the specified incident air blast wave energy.

FIG. 19 illustrates an example operational flow 500. The operationalflow includes a start operation. The operational flow includes anoperation 510. The operation 510 includes interposing between a blastevent generating an air blast wave energy and the exterior portion ofthe human body a layer of a first material positioned to initiallyreceive a specified incident air blast wave energy. The layer of thefirst material is shaped and configured to reflect a substantial portionof the specified incident air blast wave energy, and has (i) an acousticimpedance substantially mismatched to the acoustic impedance of air and(ii) a layer thickness less than about 3 mm. The operation 510 alsoincludes interposing between the blast event generating the air blastwave energy and the exterior portion of the human body a layer of secondmaterial positioned to receive at least a portion of the air blast waveenergy transmitted through the first material. The layer of the secondmaterial is shaped and configured to attenuate a substantial portion ofthe specified incident air blast wave energy transmitted through thelayer of the first material utilizing an inelastic response, and isshaped and configured for wearing proximate to the exterior portion ofthe human body. The layer of the first material includes a front surfaceand a back surface. The layer of the second material includes a frontsurface and a back surface. At least a portion of the back surface ofthe layer of the first material is proximate to at least a portion ofthe front surface of the layer of the second material. The operationalflow includes an end operation.

In an embodiment, the operational flow 500 may be implemented byinterposing the device 101 described in conjunction with FIG. 2 betweenthe incident air blast wave energy 197-I produced by the blast event 193and the exterior body part portion 106 of the human body 105.

FIG. 20 illustrates alternative embodiments of the operational flow 500of FIG. 19. The operational flow may include at least one an additionoperation. The at least one alternative embodiment may include anoperation 520 or an operation 530. The operation 520 includessubstantially reflecting a portion the specified incident air blast waveenergy utilizing the layer of the first material. The operation 530includes substantially attenuating at least a portion of the specifiedincident air blast wave energy transmitted through the layer of thefirst material utilizing an inelastic response of the layer of thesecond material.

FIG. 21 illustrates an environment 600 that includes a cross-sectionalview of an example device 601. The device includes a layer of aballistic material 610 shaped and configured to substantially attenuateenergy of an object (not illustrated) impacting an external portion of ahuman body. For example, the impacting object may include a ballistic,blunt force, or shrapnel object. The device includes the air blast waveenergy protection device 101 that includes the layer of the firstmaterial 110 and the layer of the second material 120. The layer of thefirst material 110 is shaped and configured to reflect a substantialportion of a specified incident air blast wave energy 197-I. The layerof the first material has (i) an acoustic impedance substantiallymismatched to the acoustic impedance of air and (ii) a layer thickness116 less than about 3 mm. The layer of the second material 120 is shapedand configured to attenuate a substantial portion of the specifiedincident air blast wave energy transmitted 197-T through the layer ofthe first material utilizing an inelastic response. The layer of thesecond material is shaped and configured for wearing proximate to theexterior portion 106 of the human body 105.

In an embodiment of the device 601, the layer of the ballistic material610 includes a front surface 612 and a back surface 614. In anembodiment, the front surface may be considered an exterior surface ofthe ballistic material and the back surface may be considered aninterior surface of the ballistic material. The layer of the firstmaterial 110 includes the front surface 112 and the back surface 114.The layer of the second material 120 includes the front surface 122 andthe back surface 124. At least a portion of the interior surface of thelayer of the ballistic material is proximate to the front surface of thelayer of the first material, and at least a portion of the back surfaceof the layer of the first material is proximate to at least a portion ofthe front surface of the layer of the second material. In an embodimentof the device, at least a portion of the back surface of the layer ofthe first material is proximate to the front surface of the layer of theballistic material, and at least a portion of the back surface of thelayer of the ballistic material is proximate to at least a portion ofthe front surface of the layer of the second material (not illustrated).In an embodiment of the device, at least a portion of the back surfaceof the layer of the first material is proximate to the front surface ofthe layer of a second material, and at least a portion of the backsurface of the layer of the second material is proximate to at least aportion of the front surface of the layer of the ballistic material (notillustrated).

FIG. 22 illustrates a cross-sectional view of an example wearable airblast wave energy protection device 701 that may be implemented in theenvironment 100 described in conjunction with FIG. 2. FIG. 23illustrates a cross-sectional view of an alternative embodiment of thewearable air blast wave energy protection device 701 denoted as wearableair blast wave energy protection device 701.1. Continuing with FIG. 22,in an embodiment, the air blast wave energy protection device iswearable in combat situations. The wearable air blast wave energyprotection device includes the layer of the first material 110 and alayer of a second material 720. The layer of the first material includesa layer of a first material shaped and configured to reflect asubstantial portion of the specified incident air blast wave energy197-I. The layer of the first material has an acoustic impedancesubstantially mismatched to the acoustic impedance of air. The layer ofthe second material includes a layer of a second material shaped andconfigured for wearing proximate to the exterior portion 196 of thehuman body 195 as illustrated in FIG. 2. The layer of the secondmaterial has a thickness 726. The second material includes twoattenuating-regions. A first attenuating-region 720A has a firstinelastic response to the specified incident air blast wave energytransmitted 197-T through the layer of the first material. The firstattenuating-region has a thickness 726A. A second attenuating-region720B has a second inelastic response to the specified incident air blastwave energy transmitted through the layer of the first material. In analternative embodiment, the second material includes at least threeattenuating-regions. In an alternative embodiment, the second materialincludes at least six attenuating-regions. The second attenuating-regionhas a thickness 726B.

The layer of the first material 110 includes the front surface 112 andthe back surface 114. The layer of the second material 720 includes afront surface 722A and a back surface 724B. At least a portion of theback surface 114 of the layer of the first material is proximate to atleast a portion of the front surface 722A of the layer of the secondmaterial. In an embodiment, at least a portion of the back surface ofthe layer of the first material is joined or acoustically coupled to atleast a portion of the front surface of the layer of the secondmaterial.

In an embodiment, the first attenuating-region 720A is shaped andconfigured to substantially increase a duration of the specifiedincident air blast wave energy transmitted 197-T through the layer ofthe first material 110, and has a first inelastic response to thespecified incident air blast wave energy transmitted through the layerof the first material.

In an embodiment, the layer of the second material 720 includes a layerof a second material shaped and configured for wearing proximate to theexterior portion 196 of the human body 195 and having a layer thickness726 of less than about 5 cm. In an embodiment, the second inelasticresponse being substantially dissimilar from the first inelasticresponse. In an embodiment, the second inelastic response beingsubstantially similar to the first inelastic response.

In an embodiment, the layer of a second material 720 includes a layer ofa second material shaped and configured for wearing proximate to theexterior portion 106 of the human body 195 as illustrated in FIG. 2. Thesecond material includes a single region presenting a graduatedinelastic response to the specified incident air blast wave energytransmitted 197-T through the layer of the first material 110 (notillustrated). The graduated inelastic response having a range ofinelastic responses including the first inelastic response and thesecond inelastic response. Examples of a graduated inelastic responseacross a layer of acoustic attenuating material is described inUnderwater Acoustic and Shock Absorption Performance of Syntactic Foam,Technical Note 100-1 by Cuming Corporation of Avon, Mass., accessed atwww.cumingcorp.com/pdf/cumingtechnicalnote100-1.pdf (accessed Oct. 25,2010). For example, the graduated response may be provided by voids orby inclusions, such as microspheres or macrospheres, in the secondmaterial. For example, a graduated layer combining a variety of sizesand strengths is expected to effectively provide an inelastic responseto the specified incident air blast wave energy transmitted through thelayer of the first material. For example, the graduated inelasticresponse may be provided by a varying, stepped, or sawtooth structurehaving a graduated structure. As used herein for example, “graduated”may include divided by degrees, steps, or small stages of inelasticresponses to the specified incident air blast wave energy transmittedthrough the layer of the first material. As used herein for example,“graduated” may include passing continuously from one inelastic responseto another inelastic response. As used herein for example, an inelasticresponse may be “graduated” along an axis normal or incident to thefront 722A or the back 724B surface of the layer of the second material.In an embodiment, the layer of a second material includes a layer of asecond material shaped and configured for wearing proximate to anexterior portion of the human body. The second material includes asyntactic foam presenting a gradated inelastic response across the layerto the specified incident air blast wave energy transmitted through thelayer of the first material. For example, the gradated inelasticresponse may be provided by a variety of sizes or strengths ofmicrospheres or other inclusions distributed over a thickness of thelayer of the syntactic foam.

In an embodiment, the layer of a second material 720 includes a layer ofa second material shaped and configured for wearing proximate to theexterior portion 196 of the human body 195. The second material includesa first attenuating-region 720A presenting a first graduated inelasticresponse across the first attenuating-region to the specified incidentair blast wave energy transmitted 197-T through the layer of the firstmaterial 110. The second material includes a second attenuating-region720B presenting a second graduated inelastic response to the specifiedincident air blast wave energy transmitted through the layer of thefirst material. In an embodiment, the layer of a second materialincludes a layer of a second material shaped and configured for wearingproximate to an exterior portion of a human body. The second materialincludes an aggregation of attenuating-regions. The attenuating-regionsinclude first attenuating-regions having a first inelastic response tothe specified incident air blast wave energy transmitted through thelayer of the first material. The attenuating-regions include secondattenuating-regions having a second inelastic response to the specifiedincident air blast wave energy transmitted through the layer of thefirst material. In an embodiment, the layer of a second materialincludes a layer of a second material shaped and configured for wearingproximate to an exterior portion of a human body. The second materialincludes an aggregation of approximately equal volumes of at least twoattenuating-regions. The at least two attenuating-regions include firstattenuating-regions having a first inelastic response to the specifiedincident air blast wave energy transmitted through the layer of thefirst material. The at least two attenuating-regions include secondattenuating-regions having a second inelastic response to the specifiedincident air blast wave energy transmitted through the layer of thefirst material.

In an embodiment, the layer of a second material 720 includes a layer ofa second material shaped and configured for wearing proximate to theexterior portion 196 of the human body 195. The second material includesan arrangement of at least two attenuating-regions. A firstattenuating-region 720A has a first inelastic response to the specifiedincident air blast wave energy transmitted 197-T through the layer ofthe first material 110. A second attenuating-region 720B has a secondinelastic response to the specified incident air blast wave energytransmitted 197-T through the layer of the first material.

In an embodiment, the layer of a second material 720 includes a layer ofa second material shaped and configured for wearing proximate to theexterior portion 106 of the human body 105. The second material includesan arrangement of attenuating-regions of at least twoattenuating-regions. A first attenuating-region 720A has (i) a firstinelastic response to the specified incident air blast wave energytransmitted through the layer of the first material and (ii) a firstdirectional orientation 728A to the specified incident air blast waveenergy transmitted 197-T through the layer of the first material. Asecond attenuating-region 720B has (i) a second inelastic response tothe specified incident air blast wave energy transmitted through thelayer of the first material and (ii) a second directional orientation728B to the specified incident air blast wave energy transmitted throughthe layer of the first material. In an embodiment, a directionalorientation of an attenuating-region includes a directional orientationof a major or longest axis of the attenuation region. In an embodiment,the second directional orientation is at least substantially the same asthe first directional orientation. For example, FIG. 22 illustrates anembodiment where the layer of the second material 720 of the device 701includes a second directional orientation 728B of the secondattenuating-region 720B that is at least substantially the same as afirst directional orientation 728A of the first attenuating-region 720A.For example, FIG. 23 illustrates an alternative embodiment device 701.1of the device 701. The device 701.1 includes a layer of a secondmaterial 720 that includes an arrangement of at least two segments ofattenuating-regions. A first attenuating-region segment 720.1 includesan attenuating-region 720A.1 and an attenuating-region 720B.1. A secondattenuating-region segment 720.2 includes an attenuating-region 720A.2and an attenuating-region 720B.2. A third-attenuating-region segment720.3 includes an attenuating-region 720A.3 and an attenuating-region720B.3. FIG. 23 illustrates an embodiment where the thirdattenuating-region segment 720.3 of the device 701.1 includes a seconddirectional orientation 728B.3 of the second attenuating-region 720B.3substantially similar to a first directional orientation 728A.3 of thefirst attenuating-region 720A.3. In an embodiment of the device 701 orthe device 701.1, the second directional orientation being substantiallydissimilar from the first directional orientation (not illustrated). Forexample, the second directional orientation 728B.3 of the secondattenuating-region 720B.3 may be at least substantially normal to thefirst directional orientation 728A.3 of the first attenuating-region720A.3 (not illustrated). In an embodiment of the device 701 or thealternative embodiment of the device 701.1, attenuating orsub-attenuating-regions of the layer of the second material may includean arrangement of shapes each not having a substantial directionalorientation, for example, such as that illustrated in FIG. 43 for alayer of a first material 2010.

Continuing with FIG. 22, in an embodiment, the at least twoattenuating-regions are respectively formed in sub-layers each havingfront and back surfaces generally aligned with the interface between thelayer of the first material 110 and the layer of the second material 720as illustrated by FIG. 22. In an embodiment, the at least twoattenuating-regions are respectively formed in layers each having frontand back surfaces generally perpendicular to the interface between thelayer of the first material 110 and the layer of the second material 720as illustrated by FIG. 33.

Continuing with FIG. 22, in an embodiment, the layer of the secondmaterial 720 includes a layer of a second material shaped and configuredfor wearing proximate to the exterior portion 106 of the human body 105.The second material includes at least two segments respectively havingat least two attenuating-regions. A first segment of the at least twosegments includes a first attenuating-region of the at least twoattenuating-regions having a first inelastic response to the specifiedincident air blast wave energy transmitted 197-T through the layer ofthe first material. The first segment includes a secondattenuating-region of the at least two attenuating-regions having asecond inelastic response to the specified incident air blast waveenergy transmitted through the layer of the first material. For example,the first sub-layer of attenuating-regions may include theattenuating-region 720A and the attenuating-region 720B. The secondsub-layer of attenuating-regions may include another pair ofattenuating-regions.

FIG. 23 illustrates an alternative embodiment of the device 701.1. Inthis alternative embodiment, the layer of the second material 720includes a layer of a second material shaped and configured for wearingproximate to the exterior portion 106 of the human body. The secondmaterial includes at least two segments respectively havingattenuating-regions, such as a first segment 720.1, a second segment720.2, and a third segment 720.3. A first attenuating-region 720A.1 ofthe first segment 720.1 of the at least two segments has a firstinelastic response to the specified incident air blast wave energytransmitted 197-T through the layer of the first material 110. A secondattenuating-region 720B.1 of the first segment 720.1 of the at least twosegments has a second inelastic response to the specified incident airblast wave energy transmitted through the layer of the first material.

In an embodiment (not illustrated), the layer of a second material 720includes a layer of a second material shaped and configured for wearingproximate to the exterior portion 106 of the human body 105. The secondmaterial includes at least three attenuating-regions (not illustrated).The at least three attenuating-regions include a firstattenuating-region having a first inelastic response to the specifiedincident air blast wave energy transmitted 197-T through the layer ofthe first material 110. The at least three attenuating-regions include asecond attenuating-region having a second inelastic response to thespecified incident air blast wave energy transmitted through the layerof the first material. The at least three attenuating-regions include athird attenuating-region having a third inelastic response to thespecified incident air blast wave energy transmitted through the layerof the first material.

Returning to FIG. 22, in an embodiment, the layer of a second material720 includes a layer of a second material shaped and configured toinelastically attenuate the specified incident air blast wave energytransmitted 197-T through the layer of the first material 110 by atleast 3 dB, and for wearing proximate to an exterior portion of a humanbody. In an embodiment, the layer of a second material includes a layerof a second material shaped and configured to inelastically attenuatethe specified incident air blast wave energy transmitted through thelayer of the first material by at least 6 dB, and for wearing proximateto an exterior portion of a human body. In an embodiment, the layer of asecond material includes a layer of a second material shaped andconfigured to inelastically attenuate the specified incident air blastwave energy transmitted through the layer of the first material by atleast 10 dB, and for wearing proximate to an exterior portion of a humanbody. In an embodiment, the layer of a second material includes a layerof a second material shaped and configured to inelastically attenuatethe specified incident air blast wave energy transmitted through thelayer of the first material by at least 20 dB, and for wearing proximateto an exterior portion of a human body. In an embodiment, the layer of asecond material includes a layer of a second material shaped andconfigured to inelastically attenuate the specified incident air blastwave energy transmitted through the layer of the first material by atleast 30 dB, and for wearing proximate to an exterior portion of a humanbody.

In an embodiment, the wearable air blast wave energy protection device701 includes a label (not illustrated) indicating use of the device islimited to single exposure to the specified air blast wave energy 197-I.In an embodiment, the device includes an indicator configured to providea human-perceivable indication that the device has been exposed to anair blast wave energy, such as the specified incident air blast waveenergy. An embodiment of the indicator includes the indicator 191described in conjunction with FIG. 2.

In an embodiment, the device 701 includes a spall liner shaped (notillustrated) and configured to restrain at least one fragment brokenfrom the layer of the first material 110 by the specified incident airblast wave energy 197-I. For example, the spall liner may be at leastsubstantially similar to the spall liner 140 described in conjunctionwith FIGS. 5 and 6. In an embodiment, the layer of the first materialincludes the front surface 112 and the back surface 114, the layer ofthe second material 720 includes the front surface 722A and the backsurface 724B, and the spall liner 140 includes the front surface 142 andthe back surface 144. In an embodiment, at least a portion of the backsurface of the layer of the first material is proximate to at least aportion of the front surface of the spall liner, and at least a portionof the back surface of the spall liner is proximate to the front surfaceof the layer of the second material. In an embodiment, at least aportion of the back surface of the layer of the first material isproximate to at least a portion of the front surface of the spall liner,and at least a portion of the back surface of the spall liner is joinedor acoustically coupled to the front surface of the layer of the secondmaterial. For example, see FIG. 5. In an embodiment, at least a portionof the back surface of the layer of the first material is proximate toat least a portion of the front surface of the layer of the secondmaterial, and at least a portion of the back surface of the layer of thesecond material is proximate to at least a portion of the front surfaceof the spall liner. For example, see FIG. 6.

In an embodiment, the wearable air blast wave energy protection device701 includes a layer of ballistic material (not illustrated) shaped andconfigured to substantially attenuate energy of an object impacting theexterior portion of the human body. For example, the layer of ballisticmaterial may be at least substantially similar to the layer of ballisticmaterial 170 described in conjunction with FIG. 7. In an embodiment, thelayer of the first material 110 includes the front surface 112 and theback surface 114, the layer of the second material 720 includes thefront surface and the back surface, the layer of ballistic material 170includes the front surface 172 and the back surface 174. In anembodiment, at least a portion of the back surface of the layer of theballistic material is proximate to the front surface of the layer of thefirst material, and at least a portion of the back surface of the layerof the first material is proximate to at least a portion of the frontsurface of the second material. In an embodiment, at least a portion ofthe back surface of the layer of the first material is proximate to thefront surface of the layer of the ballistic material, and at least aportion of the back surface of the layer of the ballistic materialproximate to at least a portion of the front surface of the layer of thesecond material. In an embodiment, at least a portion of the backsurface of the layer of the second material is proximate to at least aportion of the front surface of the layer of the ballistic material. Inan embodiment, the wearable air blast wave energy protection deviceincludes a retaining apparatus (not illustrated) configured to hold theproximate layer of a first material and the layer of the second materialadjacent to the exterior portion of a human body.

Returning to FIG. 22, FIG. 22 illustrates an embodiment of the wearableair blast wave energy protection device 701. The device includes thelayer of the first material 110 shaped and configured to reflect asubstantial portion of a specified incident air blast wave energy. Thefirst material has an acoustic impedance substantially mismatched to theacoustic impedance of air. The device includes the layer of the secondmaterial 720 shaped and configured to inelastically attenuate thespecified incident air blast wave energy transmitted through the layerof the first material by at least 3 dB, and for wearing proximate to anexterior portion of a human body. The second material including at leasttwo attenuating-regions. The at least two attenuating-regions include afirst attenuating-region 720A having a first inelastic response to thespecified incident air blast wave energy transmitted through the layerof the first material. The at least two attenuating-regions include asecond attenuating-region 720B having a second inelastic response to thespecified incident air blast wave energy transmitted through the layerof the first material. Another embodiment of the device includes thelayer of the first material 110 shaped and configured to reflect asubstantial portion of a specified incident air blast wave energy. Thefirst material has an acoustic impedance substantially mismatched to theacoustic impedance of air. The device includes the layer of the secondmaterial 720 shaped and configured to inelastically attenuate thespecified incident air blast wave energy transmitted through the layerof the first material by at least 10 dB, and for wearing proximate to anexterior portion of a human body. The second material including at leasttwo attenuating-regions. The at least two attenuating-regions include afirst attenuating-region 720A having a first inelastic response to thespecified incident air blast wave energy transmitted through the layerof the first material. The at least two attenuating-regions include asecond attenuating-region 720B having a second inelastic response to thespecified incident air blast wave energy transmitted through the layerof the first material.

FIG. 24 illustrates an example operational flow 800. After a startoperation, the operational flow includes a reflection modeling operation810. The reflection modeling operation includes computer modeling atleast two candidate reflective materials for a first human-protectiveand primarily reflective response to a specified incident air blast waveenergy. The computer modeling of the at least two candidate reflectivematerials is at least partially based on respective acoustic impedancesof the at least two candidate reflective materials to the specifiedincident air blast wave energy. The respective acoustic impedances ofthe at least two candidate reflective materials each are substantiallymismatched to the acoustic impedance of air. The air blast wave energyincludes an air blast wave energy produced by a high intensityexplosive. In an embodiment, the specified incident air blast waveenergy includes the air blast wave 195 produced by the blast event 193creating an energy propagating across space from the blast event andillustrated as the incident air blast wave energy 197-I described inconjunction with FIG. 2. In an embodiment, the computer modelingincludes computer modeling at least two candidate reflective materialsfor a first advantageous human-protective and primarily reflectiveresponse to a specified incident air blast wave energy. The operationalflow includes a reflective material selecting operation 820. Thereflective material selecting operation includes selecting a layer of afirst material from the at least two candidate reflective materials. Theselecting is at least partially based on the computer modeling of the atleast two candidate reflective materials. For example, the selecting alayer of a first material may include selecting the layer of the firstmaterial 110 described in conjunction with FIG. 2.

The operational flow 800 includes a first attenuation modeling operation830. The first attenuation modeling operation includes computer modelingat least two candidate attenuative materials for a secondhuman-protective and primarily attenuative response to the specifiedincident air blast wave energy transmitted through the selected layer ofthe first material. The computer modeling of the at least two candidateattenuative materials is at least partially based on respectiveinelastic responses of the two candidate attenuative materials to thespecified incident air blast wave energy transmitted through theselected layer of the first material. For example, the specifiedincident air blast wave energy transmitted through the layer of thefirst material may include the specified incident air blast wave energytransmitted 197-T through the layer of the first material described inconjunction with FIG. 2. In an embodiment, the first attenuationmodeling operation includes computer modeling at least two candidateattenuative materials for a second advantageous human-protective andprimarily attenuative response to the specified incident air blast waveenergy transmitted through the selected layer of the first material. Theoperational flow includes a first attenuating-region material selectingoperation 840. The first attenuating-region material selecting operationincludes selecting a first attenuating-region material from the at leasttwo candidate attenuative materials. The selecting is at least partiallybased on the computer modeling of the at least two candidate attenuativematerials. For example, the selecting the first attenuating-regionmaterial may include selecting the first-attenuating-region 720Adescribed in conjunction with FIG. 22.

The operational flow 800 includes a second attenuation modelingoperation 850. The second attenuation modeling operation includescomputer modeling another at least two candidate attenuative materialsfor a third human-protective and primarily attenuative response to thespecified incident air blast wave energy transmitted through theselected layer of the first material. The computer modeling of theanother at least two candidate attenuative materials is at leastpartially based on respective inelastic responses of the another twocandidate attenuative materials to the specified incident air blast waveenergy transmitted through the selected layer of the first material. Forexample, at least one of the another candidate attenuative materials ofthe second attenuation modeling operation may be at least substantiallysimilar to at least one of the candidate attenuative materials of thefirst attenuation modeling operation. In an embodiment, the secondattenuation modeling operation includes computer modeling the another atleast two candidate attenuative materials for a third advantageoushuman-protective and primarily attenuative response to the specifiedincident air blast wave energy transmitted through the selected layer ofthe first material. The operational flow includes a secondattenuating-region material selecting operation 860. The secondattenuating-region material selecting operation includes selecting asecond attenuating-region material from the at least two candidateattenuative materials. The selecting is at least partially based on thecomputer modeling of the another at least two candidate attenuativematerials. For example, the selecting the second attenuating-regionmaterial may include selecting the second-attenuating-region 720Bdescribed in conjunction with FIG. 22.

The operational flow 800 includes a storage operation 870. The storageoperation includes electronically maintaining informational datacorresponding to the selected layer of the first material, the selectedfirst attenuating-region material, and the selected secondattenuating-region material. The operational flow includes an endoperation.

FIG. 25 illustrates alternative embodiments of the operational flow 800of FIG. 24. In an embodiment, the reflective material selectingoperation 820 may include at least one alternative embodiment, such asan operation 822. The operation 822 includes selecting a layer of afirst material from the at least two candidate reflective materials. Theselecting is at least partially based on a computer-implementedevaluation of the results of the computer modeling of the at least tworeflective materials. In an embodiment, the first attenuating-regionmaterial selecting operation 840 may include at least one alternativeembodiment, such as the operation 842. The operation 842 includesselecting a first attenuating-region material from the at least twocandidate attenuative materials. The selecting is at least partiallybased on a computer-implemented evaluation of the computer modeling ofthe at least two candidate attenuative materials. In an embodiment, thesecond attenuating-region material selecting operation 860 may includeat least one alternative embodiment, such as the operation 842. Theoperation 862 includes selecting a second attenuating-region materialfrom the another at least two candidate attenuative materials. Theselecting is at least partially based on a computer-implementedevaluation of the computer modeling of the another at least twoattenuative materials.

FIG. 26 illustrates alternative embodiments of the operational flow 800of FIG. 24. The operational flow 800 may include at least onealternative embodiment. The at least one alternative embodiment mayinclude an operation 870. The operation 870 may include an operation872, an operation 874, or an operation 877. The operation 872 includeselectronically transmitting the informational data corresponding to theselected first material, the selected first attenuating-region material,and the selected second attenuating-region material. For example,“electronically transmitting” may include electronically transmitting toperson or a machine the informational data corresponding to the selectedfirst material, the selected first attenuating-region material, and theselected second attenuating-region material. For example,“electronically transmitting” may include electronically transmittingvia email or an electronic network the informational data correspondingto the selected first material, the selected first attenuating-regionmaterial, and the selected second attenuating-region material.

The operation 874 includes an operation 875 and an operation 876. Theoperation 875 includes computer modeling at least two candidatearrangements of the selected first attenuating-region material and theselected second attenuating-region material into a layer of a secondmaterial providing a fourth human-protective and substantial attenuativeresponse to the specified incident air blast wave energy transmittedthrough the selected layer of the first material. In an embodiment, thefourth human-protective and substantial attenuative response includes afourth advantageous human-protective and substantial attenuativeresponse to the specified incident air blast wave energy transmittedthrough the selected layer of the first material. The operation 876includes selecting an arrangement of the selected firstattenuating-region material and the selected second attenuating-regionmaterial into the layer of the second material. The selecting is atleast partially based on a computer-implemented evaluation of thecomputer modeling of the candidate arrangements of the selected firstattenuating-region material and the selected second attenuating-regionmaterial. The operation 877 includes an operation 878 and an operation879. The operation 878 includes computer modeling at least two candidatemethods of joining the selected layer of the first material and theselected arrangement of the selected first attenuating-region materialand the selected second attenuating-region material. The computermodeling is at least partially based on providing a fifthhuman-protective response to the specified incident air blast waveenergy. In an embodiment, the fifth human-protective response includes afifth advantageous human-protective response to the specified incidentair blast wave energy. The operation 879 includes selecting a method ofjoining in response to the computer modeling of at least two candidatemethods of joining. The selecting is at least partially based on acomputer-implemented evaluation of the computer modeling of thecandidate methods of joining.

FIG. 27 illustrates an example operational flow 900 for manufacturing awearable air blast wave energy protection device. After a startoperation, the operational flow includes a reflective material receivingoperation 910. The reflective material receiving operation includesreceiving a layer of a first material shaped and configured to provide afirst advantageous human protective and primarily reflective response toa specified incident air blast wave energy. The layer of the firstmaterial selected at least partially based on a first acoustic impedanceof the first material to the specified incident air blast wave energy,and on a substantial mismatch between the first acoustic impedance andthe acoustic impedance of air. For example, the receiving the layer offirst material may include receiving the layer of first material 110described in conjunction with FIG. 4.

A first attenuating material receiving operation 920 includes receivinga first attenuating-region material shaped and configured to provide asecond advantageous human-protective and primarily attenuative responseto the specified incident air blast wave energy transmitted through thelayer of the first material. The first attenuating-region materialselected at least partially based on a first inelastic response of thefirst attenuating-region material to the specified incident air blastwave energy transmitted through the layer of the first material. Forexample, the receiving the first attenuating-region material may includereceiving the first attenuating-region material 720A described inconjunction with FIG. 22 or the first attenuating-region material 720A.1described in conjunction with FIG. 23.

A second attenuating material receiving operation 930 includes receivinga second attenuating-region material shaped and configured to provide athird advantageous human-protective and primarily attenuative responseto the specified incident air blast wave energy transmitted through thelayer of the first material. The second attenuating-region materialselected at least partially based on a second inelastic response of thesecond attenuating-region material to the specified incident air blastwave energy transmitted through the layer of the first material. Forexample, the receiving the second attenuating-region material mayinclude receiving the second attenuating-region material 720B describedin conjunction with FIG. 22 or the second attenuating-region material720B.1 described in conjunction with FIG. 23.

An arranging operation 940 includes arranging the firstattenuating-region material and the second attenuating-region materialinto a layer of a second material providing a fourth advantageoushuman-protective and substantial attenuative response to the specifiedincident air blast wave energy transmitted through the layer of thefirst material. For example, the arranging may include arranging thefirst attenuating-region material and the second attenuating-regionmaterial into a layer of a second material as described in conjunctionwith FIG. 22 or 23.

A joining operation 950 includes joining at least a portion of a backsurface of the layer of the first material to at least a portion of afront surface of the layer of the second material. In an embodiment, thejoining operation may include at least one alternative embodiment, suchas an operation 952. In the operation 952, the joining is selected toprovide a fifth advantageous human-protective joining of the layer ofthe first material and the layer of the second material to the specifiedincident air blast wave energy. The joining is also selected at leastpartially based on an attribute of the first material, an attribute ofthe second material, or an attribute of the specified incident air blastwave energy. In an embodiment, the joining operation includes joining atleast a portion of a back surface of the layer of the first material toat least a portion of a front surface of the layer of the secondmaterial to form the air blast wave energy protection device. In anembodiment, the joining operation includes adhering at least a portionof a back surface of the layer of the first material to at least aportion of a front surface of the layer of the second material. Theoperational flow includes an end operation.

FIG. 28 illustrates an alternative embodiment of the operational flow900 of FIG. 27. The operational flow 900 may include at least onealternative embodiment. The at least one alternative embodiment mayinclude an operation 962, an operation 972, an operation 974, or anoperation 976. The operation 962 includes shaping the layer of thesecond material into a configuration suitable for wearing proximate toan exterior portion of a human body. In an embodiment, the operation 962may include at least one alternative embodiment, such as an operation964 or an operation 966. The operation 964 includes shaping the layer ofthe second material into a physical form configured or user-configurablefor wearing proximate to an exterior portion of a human body. Theoperation 966 includes shaping the layer of the second material into aphysical form user-configurable for wearing proximate to an exteriorportion of a human body with substantially no air gap between the layerof the second material and the exterior portion of the human body.

The operation 972 includes attaching at least a portion of the layer ofthe first material or the layer of the second material to a retainingstrap configured to removably secure the joined first material andsecond material proximate to an exterior portion of the human body. Theoperation 974 includes attaching at least a portion of the joined layerof the first material and the layer of the second material to a carriershaped and configured to be secured proximate to an exterior portion ofthe human body. The operation 974 includes electronically receivinginformational data corresponding to the layer of the first material, thefirst attenuating-region material, the second attenuating-regionmaterial, the arrangement of the layer of a first attenuating-regionmaterial and the layer of a second attenuating-region material, and thejoining.

FIG. 29 illustrates an example operational flow 1000. The operationalflow includes a start operation. The operational flow includes anoperation 1010. The operation 1010 includes interposing between a blastevent generating an air blast wave energy and an exterior portion of ahuman body a layer of a first material shaped and configured to reflecta substantial portion of a specified incident air blast wave energy. Thefirst material has an acoustic impedance substantially mismatched to theacoustic impedance of air. The operation 1010 also includes interposingbetween the blast event generating an air blast wave energy and theexterior portion of the human body a layer of a second material shapedand configured to attenuate utilizing an inelastic response asubstantial portion of the specified incident air blast wave energytransmitted through the layer of the first material. The layer of thesecond material is shaped and configured for wearing proximate to theexterior portion of the human body. The second material includes atleast two attenuating-regions. The at least two attenuating-regionsinclude a first attenuating-region having a first inelastic response tothe specified incident air blast wave energy transmitted through thelayer of the first material. The at least two attenuating-regionsinclude a second attenuating-region having a second inelastic responseto the specified incident air blast wave energy transmitted through thelayer of the first material. The layer of the first material includes afront surface and a back surface, and the layer of the second materialincludes a front surface and a back surface. At least a portion of theback surface of the layer of the first material is proximate to at leasta portion of the front surface of the layer of the second material. Theoperational flow includes an end operation.

For example, the operational flow 1000 may be implemented by interposingthe device 701 described in conjunction with FIG. 22 between theincident air blast wave energy 197-I produced by the blast 193 and theexterior body part portion 106 of the human body 105.

FIG. 30 illustrates alternative embodiments of the operational flow 1000of FIG. 29. The operational flow may include at least one alternativeembodiment. The at least one alternative embodiment may include anoperation 1020 or an operation 1030. The operation 1020 includesreflecting a substantial portion the specified incident air blast waveenergy utilizing the layer of the first material. The operation 1030includes attenuating at least a substantial portion of the specifiedincident air blast wave energy transmitted through the layer of thefirst material utilizing the inelastic response of the layer of thesecond material.

FIG. 31 illustrates an environment 1100 that includes example device1101. The device includes the layer of the ballistic material 610described in conjunction with FIG. 21. The layer of ballistic materialis shaped and configured to substantially attenuate energy of an object(not illustrated) impacting the external portion 106 of the human body105. The device 1101 includes the device 701 described in conjunctionwith FIG. 22 or FIG. 23. The device 701 includes the layer of the firstmaterial 110 shaped and configured to reflect a substantial portion ofthe specified incident air blast wave energy 197-I. The first materialhas an acoustic impedance substantially mismatched to the acousticimpedance of air. The device includes the layer of the second material720 shaped and configured to attenuate a substantial portion of thespecified incident air blast wave energy transmitted 197-T through thelayer of the first material utilizing an inelastic response. The layerof the second material is also shaped and configured for wearingproximate to the external portion of the human body. The second materialincludes at least two attenuating-regions. The at least twoattenuating-regions include the first attenuating-region 720A (notillustrated) having a first inelastic response to the specified incidentair blast wave energy transmitted through the layer of the firstmaterial. The at least two attenuating-regions include the secondattenuating-region 720B (not illustrated) having a second inelasticresponse to the specified incident air blast wave energy transmittedthrough the layer of the first material.

The layer of the ballistic material 610 includes the front surface 612and the back surface 614. In an embodiment, the front surface may beconsidered an exterior surface of the ballistic material and the backsurface may be considered an interior surface of the ballistic material.The layer of the first material 110 includes the front surface 112 andthe back surface 114. The layer of the second material 720 includes thefront surface 722 and the back surface 724. In an embodiment of thedevice 1101, at least a portion of the interior surface of the layer ofthe ballistic material is proximate to the front surface of the layer ofthe first material, and at least a portion of the back surface of thelayer of the first material is proximate to at least a portion of thefront surface of the layer of the second material. In an embodiment ofthe device, at least a portion of the back surface of the layer of thefirst material is proximate to the front surface of the layer of theballistic material, and at least a portion of the back surface of thelayer of the ballistic material is proximate to at least a portion ofthe front surface of the layer of the second material (not illustrated).In an embodiment of the device, at least a portion of the back surfaceof the layer of the first material is proximate to the front surface ofthe layer of a second material, and at least a portion of the backsurface of the layer of the second material is proximate to at least aportion of the front surface of the layer of the ballistic material (notillustrated).

FIG. 32 illustrates a cross-sectional view of an example wearable airblast wave energy protection device 1301 that may be implemented in theenvironment 100 described in conjunction with FIG. 2. FIG. 33illustrates a cross-sectional view of an alternative embodiment of thewearable air blast wave energy protection device 1301, which is denotedas wearable air blast wave energy protection device 1301.1. Continuingwith FIG. 32, in an embodiment, the wearable air blast wave energyprotection device is wearable in combat situations. The wearable airblast wave energy protection device includes the layer of the firstmaterial 110 shaped and configured to reflect a substantial portion ofthe specified incident air blast wave energy 197-I. The first materialhas a first acoustic impedance substantially mismatched to the acousticimpedance of air. The wearable air blast wave energy protection deviceincludes a layer of a second material 1320 shaped and configured forwearing proximate to the exterior portion 106 of the human body 105. Thelayer of the second material has a thickness 1326. The second materialincludes at least two attenuating-regions. The at least twoattenuating-regions include a first attenuating-region 1320A configuredto attenuate a first range of overpressures of the specified incidentair blast wave energy transmitted 197-T through the layer of the firstmaterial 110 utilizing a first inelastic response. In an embodiment, thefirst attenuating-region has a first crush profile configured toattenuate a first range of overpressures, such as 4-6 bars overpressure.For example, the first crush profile may include the crush plateau zone230 described in conjunction with FIG. 3, where the crush plateau zonecorresponds to between 4-6 bars overpressure on the vertical axis forstress. The first attenuating-region includes a front surface 1322A anda back surface 1324A. The at least two attenuating-regions include asecond attenuating-region 1320B configured to attenuate a second rangeof overpressures of the specified incident air blast wave energytransmitted through the layer of the first material utilizing a secondinelastic response. In an embodiment, the second attenuating region hassecond crush profile configured to attenuate a second range ofoverpressures, such as 2-4 bars overpressure. For example, the secondcrush profile may include the crush plateau zone 230 described inconjunction with FIG. 3, where the crush plateau zone corresponds tobetween 2-4 bars overpressure on the vertical axis for stress. Thesecond attenuating-region includes a front surface 1322B and a backsurface 1324B.

The layer of the first material 110 includes a front surface 112 and aback surface 114. The layer of the second material includes the frontsurface 1322A and the back surface 1324B. At least a portion of the backsurface of the layer of the first material is proximate to at least aportion of the front surface of the layer of the second material.

In an embodiment, the at least two attenuating-regions are respectivelyformed in sub-layers each having front and back surfaces generallyaligned with the interface between the layer of the first material 110and the layer of the second material 1320 as illustrated by FIG. 32. Inan embodiment, the at least two attenuating-regions are respectivelyformed in layers each having front and back surfaces generallyperpendicular to the interface between the layer of the first material110 and the layer of the second material 1320 as illustrated by FIG. 33.

In an embodiment, the first material 110 includes at least tworeflective-regions. The at least two reflective-regions include a firstreflective-region having a first acoustic impedance substantiallymismatched to the acoustic impedance of air. The at least tworeflective-regions include a second reflective-region having a secondacoustic impedance substantially less than the first acoustic impedance.For example, FIGS. 42 and 43 below respectively illustrate a firstreflective region 2010A and a second reflective region 2010B, and afirst reflective-region 2010A.1 and a second reflective-region 2010B.1.

Continuing with FIG. 32, in an embodiment, the second material 1320includes at least two attenuating-regions. The at least twoattenuating-regions include a first attenuating-region 1310A configuredto attenuate utilizing a first graduated inelastic response a firstrange of overpressures of the specified incident air blast wave energytransmitted 197-T through the layer of the first material 110. The atleast two attenuating-regions include a second attenuating-region 1310Bconfigured to attenuate a second range of overpressures of the specifiedincident air blast wave energy transmitted through the layer of thefirst material utilizing a second inelastic response. In an embodimentof this embodiment, the layer second material includes at least twoattenuating-regions. The at least two attenuating-regions include afirst attenuating-region 1310A configured to attenuate utilizing a firstgraduated inelastic response a first range of overpressures of thespecified incident air blast wave energy transmitted 197-T through thelayer of the first material 110. The at least two attenuating-regionsinclude a second attenuating-region 1310B configured to attenuateutilizing a second graduated inelastic response a second range ofoverpressures of the specified incident air blast wave energytransmitted through the layer of the first material.

Continuing with FIG. 33, in an embodiment, the second material 1320includes an aggregation of at least two attenuating-regions. The atleast two attenuating-regions include first attenuating-regions 1320A[illustrated as attenuating-regions 1320A.1, 1320A.2, 1320A.3, and1320A.4] configured to attenuate utilizing a first inelastic response afirst range of overpressures of the specified incident air blast waveenergy transmitted 197-T through the layer of the first material 110.The at least two attenuating-regions include second attenuating-regions1320B [illustrated as attenuating-regions 1320B.1, 1320B.2, and 1320B.3]shaped and configured to attenuate utilizing a second inelastic responsea second range of overpressures of the specified incident air blast waveenergy transmitted through the layer of the first material. For example,the first attenuating-regions and the second attenuating-regions may bearranged like a stack of alternating cards. For example, the firstattenuating-regions and the second attenuating-regions may be arrangedor aggregated like chocolate chips and raisins in a cookie dough mixtureor in a lumpy cake mixture. In an embodiment, the second materialincludes a second material including an aggregation of approximatelyequal volumes of at least two attenuating-regions. The at least twoattenuating-regions include first attenuating-regions configured toattenuate utilizing a first inelastic response a first range ofoverpressures of the specified incident air blast wave energytransmitted through the layer of the first material. The at least twoattenuating-regions include second attenuating-regions configured toattenuate utilizing a second inelastic response a second range ofoverpressures of the specified incident air blast wave energytransmitted through the layer of the first material.

Returning to FIG. 32, in an embodiment, the second material 1320includes at least two attenuating-regions. The at least twoattenuating-regions include first attenuating-region 1320A configured toattenuate a first range of overpressures and to substantially increase aduration of the specified incident air blast wave energy transmitted197-T through the layer of the first material 110 utilizing a firstinelastic response. The at least two attenuating-regions includes secondattenuating-region 1320B is configured to attenuate a second range ofoverpressures of the specified incident air blast wave energytransmitted through the layer of the first material utilizing a secondinelastic response.

In an embodiment of the second material 1320, the firstattenuating-region 1320A is more stiff than the secondattenuating-region 1320B. The stiffer first attenuating-region ispositioned within the device 1301 to receive the specified incident airblast wave energy transmitted 197-T through the layer of the firstmaterial 110 before the softer second attenuating-region. In anembodiment of the second material, the first attenuating-region is moresoft than the second attenuating-region 1320B. The softer firstattenuating-region is positioned in the device 1301 to receive thespecified incident air blast wave energy transmitted 197-T through thelayer of the first material 110 before the stiffer secondattenuating-region.

In an embodiment, a first attenuating-region 1320A is configured toattenuate overpressures between approximately 0.3 bar and 1 bar of thespecified incident air blast wave energy transmitted 197-T through thelayer of the first material 110 utilizing a first inelastic response. Asecond-region 1320B is configured to attenuate overpressures betweenapproximately 0.1 bar and 0.3 bar of the specified incident air blastwave energy transmitted through the layer of the first materialutilizing a second inelastic response. In an embodiment, a firstattenuating-region is configured to attenuate overpressures betweenapproximately 0.6 bar and approximately 2 bar of the specified incidentair blast wave energy transmitted through the layer of the firstmaterial utilizing a first inelastic response. A secondattenuating-region is configured to attenuate overpressures betweenapproximately 0.2 bar and 0.6 bar of the specified incident air blastwave energy transmitted through the layer of the first materialutilizing a second inelastic response. In an embodiment, a firstattenuating-region is configured to attenuate overpressures betweenapproximately 1.2 bar and 4 bar of the specified incident air blast waveenergy transmitted through the layer of the first material utilizing afirst inelastic response. A second attenuating-region is configured toattenuate overpressures between approximately 0.4 bar and 1.2 bar of thespecified incident air blast wave energy transmitted through the layerof the first material utilizing a second inelastic response. In anembodiment, a first attenuating-region is configured to attenuateoverpressures between approximately 1.8 bar and 6 bar of the specifiedincident air blast wave energy transmitted through the layer of thefirst material utilizing a first inelastic response. A secondattenuating-region is configured to attenuate overpressures betweenapproximately 0.6 bar and 1.8 bar of the specified incident air blastwave energy transmitted through the layer of the first materialutilizing a second inelastic response. In an embodiment, a firstattenuating-region is configured to attenuate overpressures betweenapproximately 2.4 bar and 8 bar of the specified incident air blast waveenergy transmitted through the layer of the first material utilizing afirst inelastic response. A second attenuating-region is configured toattenuate overpressures between approximately 0.8 bar and 2.4 bar of thespecified incident air blast wave energy transmitted through the layerof the first material utilizing a second inelastic response. In anembodiment, a first attenuating-region is configured to attenuateoverpressures between approximately 3 bar and 10 bar of the specifiedincident air blast wave energy transmitted through the layer of thefirst material utilizing a first inelastic response. A secondattenuating-region is configured to attenuate overpressures betweenapproximately 1 bar and 3 bar of the specified incident air blast waveenergy transmitted through the layer of the first material utilizing asecond inelastic response.

In an embodiment, the layer of the second material 1320 includes a layerof a second material shaped and configured for wearing proximate to theexterior portion 106 of the human body 105. The second materialincluding an arrangement of attenuating-regions. A firstattenuating-region 1320A of the arrangement of attenuating-regionshaving (i) a first inelastic response to the specified incident airblast wave energy transmitted 197-T through the layer of the firstmaterial 110 and (ii) a first directional orientation to the specifiedincident air blast wave energy transmitted through the layer of thefirst material. A second attenuating-region of the arrangement ofattenuating-regions having (i) a second inelastic response to thespecified incident air blast wave energy transmitted through the layerof the first material and (ii) a second directional orientation to thespecified incident air blast wave energy transmitted through the layerof the first material. In an embodiment, a directional orientation of anattenuating-region includes a directional orientation of a major orlongest axis of the attenuation region. In an embodiment, the seconddirectional orientation is at least substantially the same as the firstdirectional orientation. For example, FIG. 32 illustrates an embodimentwhere the layer of the second material 1320 of the device 1301 includesa second directional orientation 1328B of the second attenuating-region1320B being substantially similar to a first directional orientation1328A of the first attenuating-region 1320A. In an embodiment, the layerof the second material 1320 of the device 1301 includes a seconddirectional orientation 1328B of the second attenuating-region 1320Bsubstantially dissimilar from a first directional orientation 1328A ofthe first attenuating-region 1320A (not illustrated).

In an embodiment, the at least two attenuating-regions of the layer ofthe second material 1320 include a first attenuating-region 1320A havinga first yield stress σ_(y1) and configured to attenuate a first range ofoverpressures of the specified incident air blast wave energytransmitted 197-T through the layer of the first 110 material utilizinga first inelastic response. The at least two attenuating-regions includea second attenuating-region having a second yield stress σ_(y2) andconfigured to attenuate a second range of overpressures of the specifiedincident air blast wave energy transmitted through the layer of thefirst material utilizing a second inelastic response. In an embodiment,σ_(y1)/σ_(y2) equals approximately 3. In an embodiment, σ_(y1)/σ_(y2)equals approximately 6. In an embodiment, σ_(y1)/σ_(y2) equalsapproximately 10. In an embodiment, “approximately” describes a range of+/−5%. In an embodiment, “approximately” describes a range of +/−10%. Inan embodiment, “approximately” describes a range of +/−15%.

FIG. 33 illustrates the alternative embodiment 1301.1 of the device1301. The device 1301.1 includes a layer of a second material 1320 thatincludes an arrangement of at least two segments of attenuating-regions.The at least two segments of attenuating-regions are illustrated as afirst attenuating-region segment 1320.1, a second attenuating-regionsegment 1320.2, and a third attenuating-region segment 1320.3. In anembodiment, an attenuating-region segment of the at least two segmentsof attenuating-regions may include at least two portions. For example,the first attenuating-region segment 1320.1 includes a firstattenuating-region portion 1320A.1 and a second attenuating-regionportion 1320B.1. The first attenuating-region portion has (i) a firstinelastic response to the specified incident air blast wave energytransmitted 197-T through the layer of the first material 110 and (ii) afirst directional orientation 1328A.1 to the specified incident airblast wave energy transmitted through the layer of the first material.The second attenuating-region segment includes (i) a second inelasticresponse to the specified incident air blast wave energy transmittedthrough the layer of the first material and (ii) a second directionalorientation 1328B.1 to the specified incident air blast wave energytransmitted through the layer of the first material. FIG. 33 illustratesan embodiment where the second directional orientation 1328B.1 beingsubstantially similar to the first directional orientation 1328A.1. Inan embodiment, the second directional orientation 1328B.1 beingsubstantially dissimilar from the first directional orientation 1328A.1(not illustrated). For example, the second directional orientation1328B.1 may be at least substantially normal to the first directionalorientation 1328A.1. In an embodiment of the device 1301 or the device1301.1, the arrangement of the two segments of attenuating-regions mayinclude an arrangement of shapes not having a substantial directionalorientation, for example, such as that illustrated in FIG. 43 for alayer of a first material 2010.

Returning to FIG. 32, in an embodiment of the device 1301, the layer ofthe second material 1320 includes a layer of a second materialconfigured for wearing proximate to the exterior portion 106 of thehuman body 105. The second material includes at least threeattenuating-regions. The at least three attenuating-regions include afirst attenuating-region 1320A configured to attenuate a first range ofoverpressures of the specified incident air blast wave energytransmitted 197-T through the layer of the first material 110 utilizinga first inelastic response. For example, the first attenuating-regionmay be configured to attenuate overpressures between approximately 6 and8 bars. The at least three attenuating-regions include a secondattenuating-region 1320B of the at least three attenuating-regionsconfigured to attenuate a second range of overpressures of the specifiedincident air blast wave energy transmitted through the layer of thefirst material utilizing a second inelastic response. For example, thesecond attenuating-region may be configured to attenuate overpressuresbetween approximately 4 and 6 bars. The at least threeattenuating-regions include a third attenuating-region (not illustrated)configured to attenuate a third range of overpressures of the specifiedincident air blast wave energy transmitted through the layer of thefirst material utilizing a third inelastic response. For example, thethird attenuating-region may be configured to attenuate overpressuresbetween approximately 2 and 4 bars. The first attenuating-region 1320Aincludes a front surface 1322A and a back surface 1324A, the secondattenuating-region 1320B includes a front surface 1322B and a backsurface 1324B, and the third attenuating-region (not illustrated)includes a front surface (not illustrated) and a back surface (notillustrated). At least a portion of the back surface of the firstattenuating-region is proximate to at least a portion of the frontsurface of the second attenuating-region, and at least a portion of theback surface of the second attenuating-region is proximate to at least aportion of the front surface of the third attenuating-region.

In an embodiment of the layer of the second material 1320 that includesat least three attenuating-regions, the first attenuating-region of theat least three attenuating-regions is configured to attenuate a firstrange of overpressures between approximately 0.3 bar and 1 bar of thespecified incident air blast wave energy transmitted 197-T through thelayer of the first material 110 utilizing a first inelastic response.The second attenuating-region of the at least three attenuating-regionsis configured to attenuate a second range of overpressures betweenapproximately 0.2 bar and 0.6 bar. The third attenuating-region of theat least three attenuating-regions is configured to attenuate a thirdrange of overpressures between approximately 0.1 bar and 0.3 bar. In anembodiment of the layer of the second material 1320 that includes atleast three attenuating-regions, the first attenuating-region of the atleast three attenuating-regions is configured to attenuate a first rangeof overpressures between approximately 0.6 bar and 2 bar of thespecified incident air blast wave energy transmitted through the layerof the first material utilizing a first inelastic response. The secondattenuating-region is configured to attenuate a second range ofoverpressures between approximately 0.4 bar and 1.2 bar. The thirdattenuating-region is configured to attenuate a third range ofoverpressures between approximately 0.2 bar and 0.6 bar. In anembodiment of the layer of the second material 1320 that includes atleast three attenuating-regions, the first attenuating-region of the atleast three attenuating-regions is configured to attenuate a first rangeof overpressures between approximately 1.2 bar and 4.0 bar of thespecified incident air blast wave energy transmitted through the layerof the first material utilizing a first inelastic response. The secondattenuating-region is configured to attenuate a second range ofoverpressures between approximately 0.8 bar and 2.4 bar. The thirdattenuating-region is configured to attenuate a third range ofoverpressures between approximately 0.4 bar and 1.2 bar. In anembodiment of the layer of the second material 1320 that includes atleast three attenuating-regions, the first attenuating-region of the atleast three attenuating-regions is configured to attenuate a first rangeof overpressures between approximately 1.8 bar and 6 bar of thespecified incident air blast wave energy transmitted through the layerof the first material utilizing a first inelastic response. The secondattenuating-region is configured to attenuate a second range ofoverpressures between approximately 1.2 bar and 4.2 bar. The thirdattenuating-region is configured to attenuate a third range ofoverpressures between approximately 0.6 bar and 1.8 bar. In anembodiment of the layer of the second material 1320 that includes atleast three attenuating-regions, the first attenuating-region of the atleast three attenuating-regions is configured to attenuate a first rangeof overpressures between approximately 2.4 bar and 8.0 bar of thespecified incident air blast wave energy transmitted through the layerof the first material utilizing a first inelastic response. The secondattenuating-region is configured to attenuate a second range ofoverpressures between approximately 1.6 bar and 4.8. The thirdattenuating-region is configured to attenuate a third range ofoverpressures between approximately 0.8 bar and 2.4 bar. In anembodiment of the layer of the second material 1320 that includes atleast three attenuating-regions, the first attenuating-region of the atleast three attenuating-regions is configured to attenuate a first rangeof overpressures between approximately 3 bar and 10 bar of the specifiedincident air blast wave energy transmitted through the layer of thefirst material utilizing a first inelastic response. The secondattenuating-region is configured to attenuate a second range ofoverpressures between approximately 2 bar and 6 bar. The thirdattenuating-region is configured to attenuate a third range ofoverpressures between approximately 1 bar and 3 bar.

In an embodiment of the layer of the second material 1320 that includesat least three attenuating-regions, the at least threeattenuating-regions include a first attenuating-region having a firstyield stress σ_(y1) and configured to attenuate a first range ofoverpressures of the specified incident air blast wave energytransmitted through the layer of the first material utilizing a firstinelastic response. The at least three attenuating-regions include asecond attenuating-region having a second yield stress σ_(y2) andconfigured to attenuate a second range of overpressures of the specifiedincident air blast wave energy transmitted through the layer of thefirst material utilizing a second inelastic response. The at least threeattenuating-regions include a third attenuating-region having a thirdyield stress σ_(y31) and configured to attenuate a third range ofoverpressures of the specified incident air blast wave energytransmitted through the layer of the first material utilizing a thirdinelastic response. In an embodiment of the at least threeattenuating-regions, σ_(y1)>σ_(y2>σ) _(y3). In an embodiment of the atleast three attenuating-regions, σ_(y1)>2σ_(y2), and σ_(y2)>2σ_(y3). Inan embodiment of the at least three attenuating-regions, σ_(y1)>3σ_(y2),and σ_(y2)>3σ_(y3). In an embodiment of the at least threeattenuating-regions, σ_(y1)>4σ_(y2), and σ_(y2)>4σ_(y3).

In an embodiment, the layer of the second material 1320 includes a layerof a second material shaped and configured (i) for wearing proximate tothe exterior portion 106 of the human body 105 and (ii) for a singleexposure to the specified incident air blast wave energy transmitted197-T through the layer of the first material 110. The second materialincludes attenuating-regions, illustrated as the firstattenuating-region 1320A and the second attenuating-region 1320B.

In an embodiment, the device 1301 includes a label (not illustrated)indicating use of the device is limited to a single exposure to thespecified incident air blast wave energy 197-I. In an embodiment, thedevice includes an indicator configured to provide a human-perceivableindication that the device has been exposed to an air blast wave energy,such as the specified incident air blast wave energy 197-I. Anembodiment of the indicator includes the indicator 191 described inconjunction with FIG. 4.

In an embodiment, the device 1301 includes a spall liner shaped andconfigured to restrain at least one fragment broken from the layer ofthe first material 110 by the specified incident air blast wave energy197-I. For example, the spall liner may be at least substantiallysimilar to the spall liner 140 described in conjunction with FIGS. 5 and6. In an embodiment, the layer of the first material 110 includes thefront surface 112 and the back surface 114, the layer of the secondmaterial 1320 includes the front surface 1322A and the back surface1324B, and the spall liner 140 includes the front surface 142 and theback surface 144. In an embodiment, at least a portion of the backsurface of the layer of the first material is proximate to at least aportion of the front surface of the spall liner, and at least a portionof the back surface of the spall liner is proximate to the front surfaceof the layer of the second material. In an embodiment, at least aportion of the back surface of the layer of the first material isproximate to at least a portion of the front surface of the layer of thesecond material, and at least a portion of the back surface of the layerof the second material is proximate to at least a portion of the frontsurface of the spall liner.

In an embodiment of the device 1301, the layer of the first material 110includes the front surface 112 and the back surface 114, and the layerof the second material 1320 includes a front surface 1322A and the backsurface 1324B. At least a portion of the back surface of the layer ofthe first material is joined to at least a portion of the front surfaceof the layer of the second material. In an embodiment of the device, atleast a portion of the back surface of the layer of the first materialis joined to at least a portion of the front surface of the layer of thesecond material. The joined layer of the first material and the layer ofthe second material forming an at least substantially stiff assembly. Inan embodiment of the device, at least a portion of the back surface ofthe layer of the first material is joined to at least a portion of thefront surface of the layer of the second material. The joined layer ofthe first material and the layer of the second material forming an atleast substantially flexible assembly. In an embodiment of the device,at least a portion of the back surface of the layer of the firstmaterial is acoustically coupled to at least a portion of the frontsurface of the layer of the second material. In an embodiment of thedevice, at least a portion of the back surface of the layer of the firstmaterial is proximate to at least a portion of the front surface of thelayer of the second material. The proximate first material and thesecond material are shaped and configured such that the device iswearable proximate to the exterior portion of the human body without asignificant continuous air path between a portion of the front surfaceof the first material and the exterior portion of the human body.

In an embodiment, the device 1301 includes a layer of a ballisticmaterial shaped and configured to substantially attenuate energy of anobject (not illustrated) impacting the exterior portion 106 of the humanbody 105. For example, the layer of ballistic material may be at leastsubstantially similar to the layer of ballistic material 170 describedin conjunction with FIG. 7. In an embodiment, the layer of the firstmaterial 110 includes the front surface 112 and the back surface 114,the layer of the second material 1320 includes the front surface 1322Aand the back surface 1324B, and the layer of ballistic material 170includes the front surface 172 and the back surface 174. In anembodiment, at least a portion of the back surface of the layer of theballistic material is proximate to the front surface of the layer of thefirst material, and at least a portion of the back surface of the layerof the first material is proximate to at least a portion of the frontsurface of the second material. In an embodiment, at least a portion ofthe back surface of the layer of the first material is proximate to thefront surface of the layer of the ballistic material, and at least aportion of the back surface of the layer of the ballistic materialproximate to at least a portion of the front surface of the layer of thesecond material. In an embodiment, at least a portion of the backsurface of the layer of the second material is proximate to at least aportion of the front surface of the layer of the ballistic material. Inan embodiment, the device includes a retaining apparatus (notillustrated) configured to hold the proximate layer of a first materialand the layer of the second material adjacent to the exterior portion ofa human body.

FIG. 32 and FIG. 33 illustrate an alternative embodiment of the wearableair blast wave energy protection device 1301. The device includes alayer of a first material 110 shaped and configured to reflect asubstantial portion of a specified incident air blast wave energy 197-I.The first material having a first acoustic impedance substantiallymismatched to the acoustic impedance of air. The device includes a layerof a second material shaped and configured for wearing proximate to anexterior portion of a human body. The second material including at leasttwo attenuating-regions. The at least two attenuating-regions include afirst attenuating-region [1320A of FIG. 32 or 1320A.1 of FIG. 33]configured to attenuate overpressures between approximately 1.2 bar and4 bar of the specified incident air blast wave energy transmitted 197-Tthrough the layer of the first material utilizing a first inelasticresponse. The at least two attenuating-regions include a secondattenuating-region [1320B of FIG. 32 or 1320B.1 of FIG. 33] configuredto attenuate overpressures between approximately 0.4 bar and 1.2 bar ofthe specified incident air blast wave energy transmitted through thelayer of the first material utilizing a second inelastic response. Thelayer of the first material includes a front surface and a back surface,and the layer of the second material includes a front surface and a backsurface. At least a portion of the back surface of the layer of thefirst material is proximate to at least a portion of the front surfaceof the layer of the second material.

FIG. 32 and FIG. 33 illustrate another alternative embodiment of thewearable air blast wave energy protection device 1301. The deviceincludes a layer of a first material 110 shaped and configured toreflect a substantial portion of a specified incident air blast waveenergy 197-I. The first material having a first acoustic impedancesubstantially mismatched to the acoustic impedance of air. The deviceincludes a layer of a second material shaped and configured for wearingproximate to an exterior portion of a human body. The second materialincluding at least two attenuating-regions. The at least twoattenuating-regions include a first attenuating-region [1320A of FIG. 32or 1320A.1 of FIG. 33] configured to attenuate overpressures betweenapproximately 1.8 bar and 6 bar of the specified incident air blast waveenergy transmitted 197-T through the layer of the first materialutilizing a first inelastic response. The at least twoattenuating-regions include a second attenuating-region [1320B of FIG.32 or 1320B.1 of FIG. 33] configured to attenuate overpressures betweenapproximately 0.6 bar and 1.8 bar of the specified incident air blastwave energy transmitted through the layer of the first materialutilizing a second inelastic response. The layer of the first materialincludes a front surface and a back surface, and the layer of the secondmaterial includes a front surface and a back surface. At least a portionof the back surface of the layer of the first material is proximate toat least a portion of the front surface of the layer of the secondmaterial.

FIG. 34 illustrates an example operational flow 1400. After a startoperation, the operational flow includes a reflection modeling operation1410. The reflection modeling operation includes computer modeling atleast two candidate reflective materials for a first human-protectiveand primarily reflective response to a specified incident air blast waveenergy. The computer modeling of the at least two candidate reflectivematerials is at least partially based on respective acoustic impedancesof the at least two candidate reflective materials to the specifiedincident air blast wave energy. The respective acoustic impedances ofthe at least two candidate reflective materials are each substantiallymismatched to the acoustic impedance of air. For example, the specifiedincident air blast wave energy may include the air blast wave 195produced by the blast event 193 creating an energy propagating acrossspace from the blast event and illustrated as the incident air blastwave energy 197-I described in conjunction with FIG. 2. For example, thecomputer modeling may include computer modeling at least two candidatereflective materials for a first advantageous human-protective andprimarily reflective response to a specified incident air blast waveenergy. The operational flow includes a reflective material selectingoperation 1420. The reflective material selecting operation includesselecting a layer of a first material from the at least two candidatereflective materials. The selecting is at least partially based on thecomputer modeling of the at least two candidate reflective materials.For example, the selecting a layer of a first material may includeselecting the layer of the first material 110 described in conjunctionwith FIG. 2.

The operational flow 1400 includes a first attenuation modelingoperation 1430. The first attenuation modeling operation includescomputer modeling at least two candidate attenuative materials for asecond human-protective and primarily attenuative response to thespecified incident air blast wave energy transmitted through theselected layer of the first material. The computer modeling of the atleast two candidate attenuative materials is at least partially based onrespective inelastic responses of the two candidate attenuativematerials to a first range of overpressures of the specified incidentair blast wave energy transmitted through the selected layer of thefirst material. For example, the specified incident air blast waveenergy transmitted through the layer of the first material may includethe specified incident air blast wave energy transmitted 197-T throughthe layer of the first material described in conjunction with FIG. 2.For example, the first attenuation modeling operation may includecomputer modeling at least two candidate attenuative materials for asecond advantageous human-protective and primarily attenuative responseto the specified incident air blast wave energy transmitted through theselected layer of the first material. The operational flow includes afirst attenuating-region material selecting operation 1440. The firstattenuating-region material selecting operation includes selecting afirst attenuating-region material from the at least two candidateattenuative materials. The selecting is at least partially based on thecomputer modeling of the at least two candidate attenuative materials tothe first range of overpressures. For example, the selecting the firstattenuating-region material may include selecting thefirst-attenuating-region 1320A described in conjunction with FIG. 32.

The operational flow 1400 includes a second attenuation modelingoperation 1450. The second attenuation modeling operation includescomputer modeling another at least two candidate attenuative materialsfor a third human-protective and primarily attenuative response to thespecified incident air blast wave energy transmitted through theselected layer of the first material. The computer modeling of theanother at least two candidate attenuative materials is at leastpartially based on respective inelastic responses of the another twocandidate attenuative materials to a second range of overpressures ofthe specified incident air blast wave energy transmitted through theselected layer of the first material. For example, at least one of theanother candidate attenuative materials of the second attenuationmodeling operation may be at least substantially similar to at least oneof the candidate attenuative materials of the first attenuation modelingoperation. In an embodiment, the second attenuation modeling operationincludes computer modeling the another at least two candidateattenuative materials for a third advantageous human-protective andprimarily attenuative response to the specified incident air blast waveenergy transmitted through the selected layer of the first material. Theoperational flow includes a second attenuating-region material selectingoperation 1460. The second attenuating-region material selectingoperation includes selecting a second attenuating-region material fromthe at least two candidate attenuative materials. The selecting is atleast partially based on the computer modeling of the another at leasttwo candidate attenuative materials to the second range ofoverpressures. For example, the selecting the second attenuating-regionmaterial may include selecting the second-attenuating-region 1320Bdescribed in conjunction with FIG. 32.

The operational flow 1400 includes a storage operation 1470. The storageoperation includes electronically maintaining informational datacorresponding to the selected layer of the first material, the selectedfirst attenuating-region material, and the selected secondattenuating-region material. The operational flow includes an endoperation.

FIG. 35 illustrates alternative embodiments of the operational flow 1400of FIG. 34. In an embodiment, the reflective material selectingoperation 1420 may include at least one alternative embodiment, such asan operation 1422. The operation 1422 includes selecting a layer of afirst material from the at least two candidate reflective materials. Theselecting is at least partially based on a computer-implementedevaluation of the results of the computer modeling of the at least twocandidate reflective materials. In an embodiment, the firstattenuating-region material selecting operation 1440 may include atleast one alternative embodiment, such as the operation 1442. Theoperation 1442 includes selecting a first attenuating-region materialfrom the at least two candidate attenuative materials. The selecting isat least partially based on a computer-implemented evaluation of thecomputer modeling of the at least two candidate reflective materials tothe first range of overpressures. In an embodiment, the secondattenuating-region material selecting operation 1460 may include atleast one alternative embodiment, such as the operation 1462. Theoperation 1462 includes selecting a second attenuating-region materialfrom the another at least two candidate attenuative materials. Theselecting is at least partially based on a computer-implementedevaluation of the computer modeling of the another at least twocandidate reflective materials to the second range of overpressures. Inan embodiment, the storage operation 1470 may include at least onealternative embodiment, such as the operation 1472. The operation 1472includes electronically transmitting the informational datacorresponding to the selected first material, the selected firstattenuating-region material, and the selected second attenuating-regionmaterial. In an embodiment, the operation 1472 includes electronicallytransmitting the informational data to person or a machine. In anembodiment, the operation 1470 includes electronically transmitting theinformational data via email or a network, such as the Internet.

FIG. 36 illustrates alternative embodiments of the operational flow 1400of FIG. 34. In an embodiment, the operational flow may include at leastone alternative embodiment. The at least one alternative embodiment mayinclude an operation 1480, or an operation 1490. The operation 1480includes an operation 1482 and an operation 1484.

The operation 1482 includes computer modeling at least two candidatearrangements of the selected first attenuating-region material and theselected second attenuating-region material into a layer of a secondmaterial providing a fourth human-protective and substantial attenuativeresponse to the specified incident air blast wave energy transmittedthrough the layer of the first material. In an embodiment, the providinga fourth human-protective and substantial attenuative response includesproviding a fourth advantageous human-protective and substantialattenuative response. The operation 1484 includes selecting anarrangement of the selected first attenuating-region material and theselected second attenuating-region material into the layer of the secondmaterial. The selecting is at least partially based on acomputer-implemented evaluation of the computer modeling of thecandidate arrangements of the selected first attenuating-region materialand the selected second attenuating-region material.

The operation 1490 includes an operation 1492 and an operation 1494. Theoperation 1492 includes computer modeling at least two candidate methodsof joining the selected layer of the first material and the selectedarrangement of the selected first attenuating-region material and theselected second attenuating-region material. The computer modeling is atleast partially based on providing a fifth human-protective response tothe specified incident air blast wave energy. In an embodiment, thecomputer modeling includes computer modeling is at least partially basedon providing a fifth advantageous human-protective response. Theoperation 1494 includes selecting a method of joining in response to thecomputer modeling of at least two candidate methods of joining. Theselecting is at least partially based on a computer-implementedevaluation of the computer modeling of the candidate methods of joining.

FIG. 37 illustrates an example operational flow 1500 for manufacturing awearable air blast wave energy protection device. After a startoperation, the operational flow includes a reflective material receivingoperation 1510. The reflective material receiving operation includesreceiving a layer of a first material shaped and configured to provide afirst advantageous human protective and primarily reflective response toa specified incident air blast wave energy. The layer of the firstmaterial selected at least partially based on a first acoustic impedanceof the first material to the specified incident air blast wave energy,and on a substantial mismatch between the first acoustic impedance andthe acoustic impedance of air. For example, the receiving the layer offirst material may include receiving the layer of first material 110described in conjunction with FIG. 4.

A first attenuating material receiving operation 1520 includes receivinga first attenuating-region material shaped and configured to provide asecond advantageous human-protective and primarily attenuative responseto the specified incident air blast wave energy transmitted through thelayer of the first material. The first attenuating-region materialselected at least partially based on a first inelastic response of thefirst attenuating-region material to a first range of overpressures ofthe specified incident air blast wave energy transmitted through thelayer of the first material. For example, the receiving the firstattenuating-region material may include receiving the firstattenuating-region material 1320A described in conjunction with FIG. 32or the first attenuating-region material 1320A.1 described inconjunction with FIG. 33.

A second attenuating material receiving operation 1530 includesreceiving a second attenuating-region material shaped and configured toprovide a third advantageous human-protective and primarily attenuativeresponse to the specified incident air blast wave energy transmittedthrough the layer of the first material. The second attenuating-regionmaterial selected at least partially based on a second inelasticresponse of the second attenuating-region material to a second range ofoverpressures of the specified incident air blast wave energytransmitted through the layer of the first material. For example, thereceiving the second attenuating-region material may include receivingthe second attenuating-region material 1320B described in conjunctionwith FIG. 32 or the second attenuating-region material 1320B.1 describedin conjunction with FIG. 33.

An arranging operation 1540 includes arranging the firstattenuating-region material and the second attenuating-region materialinto a layer of a second material providing a fourth advantageoushuman-protective and substantial attenuative response to the specifiedincident air blast wave energy transmitted through the layer of thefirst material. For example, the arranging may include arranging thefirst attenuating-region material and the second attenuating-regionmaterial into a layer of a second material as described in conjunctionwith FIG. 32 or 33.

A joining operation 1550 includes joining at least a portion of a backsurface of the layer of the first material to at least a portion of afront surface of the layer of the second material. In an embodiment, thejoining operation may include at least one alternative embodiment, suchas the operation 1552. The operation 1552 includes joining at least aportion of a back surface of the layer of the first material to at leasta portion of a front surface of the layer of the second material. Thejoining selected to provide a fifth advantageous human-protectivejoining of the layer of the first material and the layer of the secondmaterial to the specified incident air blast wave energy. The joiningselected at least partially based on an attribute of the first material,an attribute of the second material, or an attribute of the specifiedincident air blast wave energy. In an embodiment, the joining operationincludes joining at least a portion of a back surface of the layer ofthe first material to at least a portion of a front surface of the layerof the second material to form the air blast wave energy protectiondevice. In an embodiment, the joining operation includes adhering atleast a portion of a back surface of the layer of the first material toat least a portion of a front surface of the layer of the secondmaterial. The operational flow includes an end operation.

FIG. 38 illustrates an alternative embodiment of the operational flow1500 of FIG. 37. The operational flow may include at least onealternative embodiment, illustrated as an operation 1560. The operation1560 may include an operation 1562, an operation 1572, an operation1574, or an operation 1576. The operation 1562 includes shaping thelayer of the second material into a configuration suitable for wearingproximate to an exterior portion of a human body. The operation 1562 mayinclude at least one alternative embodiment, such as an operation 1564or an operation 1566. The operation 1564 includes shaping the layer ofthe second material into a physical form configured or user-configurablefor wearing proximate to an exterior portion of a human body. In anembodiment, the operation 1566 includes shaping the layer of the secondmaterial into a physical form user-configurable for wearing proximate toan exterior portion of a human body with substantially no air gapbetween the layer of the second material and the exterior portion of thehuman body.

The operation 1572 includes attaching at least a portion of the layer ofthe first material or the layer of the second material to a retainingstrap configured to removably secure the joined first material andsecond material proximate to an exterior portion of the human body. Theoperation 1574 includes attaching at least a portion of the joined layerof the first material and the layer of the second material to a carriershaped and configured to be secured proximate to an exterior portion ofthe human body. The operation 1576 includes electronically receivinginformational data corresponding to the layer of the first material, thefirst attenuating-region material, the second attenuating-regionmaterial, the arrangement of the first attenuating-region material andthe second attenuating-region material into the layer of the secondmaterial, and the joining.

FIG. 39 illustrates an example operational flow 1600. The operationalflow includes a start operation. The operational flow includes anoperation 1610. The operation 1610 includes interposing between a blastevent generating an air blast wave energy and an exterior portion of ahuman body a layer of a first material shaped and configured to reflecta substantial portion of a specified incident air blast wave energy. Thefirst material has an acoustic impedance substantially mismatched to theacoustic impedance of air. The operation 1610 also includes interposinga layer of a second material shaped and configured for wearing proximateto an exterior portion of a human body. The second material includes atleast two attenuating-regions. The at least two attenuating-regionsinclude a first attenuating-region configured to attenuate a first rangeof overpressures of the specified incident air blast wave energytransmitted through the layer of the first material utilizing a firstinelastic response. The at least two attenuating-regions include asecond attenuating-region is configured to attenuate a second range ofoverpressures of the specified incident air blast wave energytransmitted through the layer of the first material utilizing a secondinelastic response. The layer of the first material includes a frontsurface and a back surface, and the layer of the second materialincludes a front surface and a back surface. At least a portion of theback surface of the layer of the first material is proximate to at leasta portion of the front surface of the layer of the second material. Theoperational flow includes an end operation.

For example, the operational flow 1600 may be implemented by interposingthe device 1301 described in conjunction with FIG. 32 between theincident air blast wave energy 197-I produced by the blast 193 and theexterior body part portion 106 of the human body 105.

FIG. 40 illustrates alternative embodiments of the operational flow 1600of FIG. 39. The operational flow may include at least one alternativeembodiment. The at least one alternative embodiment may include anoperation 1620 or an operation 1630. The operation 1620 includessubstantially reflecting a portion the specified incident air blast waveenergy utilizing the layer of the first material. The operation 1630includes substantially attenuating at least a portion of the specifiedincident air blast wave energy transmitted through the layer of thefirst material utilizing the inelastic response of the layer of thesecond material.

FIG. 41 illustrates an environment 1700 that includes an example device1701. The device includes the layer of the ballistic material 610described in conjunction with FIG. 21. The layer of ballistic materialis shaped and configured to substantially attenuate energy of an object(not illustrated) impacting the external portion 106 of the human body105. The device 1701 includes the device 1301 described in conjunctionwith FIG. 32 or 1301.1 described in conjunction with FIG. 33. The device1701 includes the layer of a first material 110 shaped and configured toreflect a substantial portion of a specified incident air blast waveenergy 197-T. The layer of the first material has an acoustic impedancesubstantially mismatched to the acoustic impedance of air. The deviceincludes the layer of the second material 1320 shaped and configured forwearing proximate to the exterior portion of the human body. The secondmaterial includes at least two attenuating-regions. The at least twoattenuating-regions include a first attenuating-region 1320A (notillustrated by FIG. 41) configured to attenuate a first range ofoverpressures of the specified incident air blast wave energytransmitted 197-T through the layer of the first material utilizing afirst inelastic response. The at least two attenuating-regions include asecond attenuating-region 1320B (not illustrated by FIG. 41) configuredto attenuate a second range of overpressures of the specified incidentair blast wave energy transmitted through the layer of the firstmaterial utilizing a second inelastic response.

The layer of the ballistic material 610 includes the front surface 612and the back surface 614. In an embodiment, the front surface may beconsidered an exterior surface of a ballistic material and the backsurface may be considered an interior surface of the ballistic material.The layer of the first material 110 includes the front surface 112 andthe back surface 114. The layer of the second material 1320 includes thefront surface 1322 and the back surface 1324. In an embodiment, at leasta portion of the back surface of the layer of the ballistic material isproximate to the front surface of the layer of the first material, andat least a portion of the back surface of the layer of the firstmaterial is proximate to at least a portion of the front surface of thelayer of the second material. In an embodiment of the device, at least aportion of the back surface of the layer of the first material isproximate to the front surface of the layer of the ballistic material,and at least a portion of the back surface of the layer of the ballisticmaterial is proximate to at least a portion of the front surface of thelayer of the second material (not illustrated). In an embodiment of thedevice, at least a portion of the back surface of the layer of the firstmaterial is proximate to the front surface of the layer of a secondmaterial, and at least a portion of the back surface of the layer of thesecond material is proximate to at least a portion of the front surfaceof the layer of the ballistic material (not illustrated).

FIG. 42 illustrates a cross-sectional view of an example wearable airblast wave energy protection device 2001 that may be implemented in theenvironment 100 described in conjunction with FIG. 2. FIG. 43illustrates a cross-sectional view of an alternative embodiment of thewearable air blast wave energy protection device 2001, which is denotedas wearable air blast wave energy protection device 2001.1. Continuingwith FIG. 42, in an embodiment, the wearable air blast wave energyprotection device is wearable in combat situations. The device includesa layer of a first material 2010 shaped and configured to reflect asubstantial portion of the specified incident air blast wave energy197-I. The layer of the first material has a thickness 116. The firstmaterial includes at least two reflective-regions. The at least tworeflective-regions include a first reflective-region 2010A having afirst acoustic impedance Z₁ mismatched to the acoustic impedance of airZ_(A). In an embodiment, the first reflective region has a thickness2016A. The at least two reflective-regions include a secondreflective-region 2010B a second acoustic impedance Z₂ less than thefirst acoustic impedance Z₁. In an embodiment, the secondreflective-region has a thickness 2016B. The device includes a layer ofa second material 2020 shaped and configured to attenuate a substantialportion of the specified incident air blast wave energy transmitted197-T through the layer of the first material utilizing an inelasticresponse. The layer of the second material is shaped and configured forwearing proximate to the exterior portion 106 of the human body 105. Forexample, the layer of the second material may be at least substantiallysimilar to the layer of the second material 120 described in conjunctionwith FIG. 2.

The first reflective-region 2010A includes a front surface 2012A and aback surface 2014A. The second reflective-region includes a frontsurface 2012B and a back surface 2014B. The layer of the first material2010 includes the front surface 2012A of the first reflective-region anda back surface 2014B of the second reflective-region. The layer of thesecond material 2020 includes a front surface 2022 and a back surface2024. At least a portion of the back surface of the layer of the firstmaterial is proximate to at least a portion of the front surface of thelayer of the second material.

In an embodiment, Z₁/Z₂ equals approximately 2. In an embodiment, Z₁/Z₂equals approximately 3. In an embodiment, Z₁/Z₂ equals approximately 5.In an embodiment, Z₁/Z₂ equals approximately 10. In an embodiment, Z₁/Z₂equals approximately 30.

In an embodiment, the at least two reflective regions of the firstmaterial 2010 include a first reflective-region having a first acousticimpedance Z₁ substantially mismatched to the acoustic impedance of airZ_(A). The at least two reflective-regions include a secondreflective-region having a second acoustic impedance Z₂ substantiallyless than the first acoustic impedance Z₁ and substantially mismatchedto the acoustic impedance of air Z_(A).

In an embodiment, the at least two reflective-regions of the firstmaterial 2010 include a first reflective-region 2010A having a firstacoustic impedance Z₁ mismatched to the acoustic impedance of air Z_(A)and a first directional orientation 2028A to the specified incident airblast wave energy 197-I. The at least two reflective-regions of thefirst material include a second reflective-region 2010B having a secondacoustic impedance Z₂ less than the first acoustic impedance Z₁ and asecond directional orientation 2028B to the specified incident air blastwave energy. In an embodiment, the second directional orientation issubstantially similar to the first directional orientation. In anembodiment, the second directional orientation is substantiallydissimilar from the first directional orientation.

In an embodiment, the layer of first material 2010 includes a layer of afirst material shaped and configured to reflect a substantial portion ofa specified incident air blast wave energy 197-I. The first materialincludes an arrangement of at least two reflective-regions. For example,the at least two reflective-regions may include the firstreflective-region 2010A and the second reflective-region 2010B may bearranged into at least substantially parallel sub-layers that aregenerally oriented normal to an anticipated path of the specifiedincident air blast wave energy as illustrated by FIG. 42. For example,the at least two reflective-regions may include the firstreflective-region 2010A and the second reflective-region 2010B placedinto an arrangement of pairs of regions ([2010A.1,2010B.1][2010A.2,2010B.2] [2010A.3,2010B.3]), each region not having asubstantial directional orientation as illustrated by FIG. 43. Forexample, the at least two reflective-regions may include the firstreflective-region 2010A and the second reflective-region 2010B arrangedinto at least substantially parallel regions that are generally orientedparallel to an anticipated path of the specified incident air blast waveenergy, such as for example illustrated for the attenuating-regions 1320as illustrated by FIG. 33. For example, the at least tworeflective-regions may include the first reflective-region 2010A and thesecond reflective-region 2010B arranged into regions that are generallyoriented at an angle to an anticipated path of the specified incidentair blast wave energy (not illustrated).

Returning to FIG. 42, in an embodiment, the layer of the first material2010 includes a layer of a first material shaped and configured toreflect a substantial portion of a specified incident air blast waveenergy 197-I. The first material includes at least tworeflective-regions. A first reflective-region 2010A of the at least tworeflective-regions has a first acoustic impedance substantiallymismatched to the acoustic impedance of air and a first directionalorientation 2028A to the specified incident air blast wave energy. Asecond reflective-region 2010B the at least two reflective-regions has asecond acoustic impedance substantially less than the first acousticimpedance and a second directional orientation 2028B to the specifiedincident air blast wave energy.

In an embodiment, the at least two reflective-regions are respectivelyformed in sub-layers each having front and back surfaces generallyaligned with the interface between the layer of the first material 2010and the layer of the second material 2020 as illustrated by FIG. 42. Inan embodiment, the at least two reflective-regions are respectivelyformed in layers each having front and back surfaces generallyperpendicular to the interface between the layer of the first material2010 and the layer of the second material 2020 (not illustrated).

In an embodiment, the layer of the first material 2010 includes a layerof a first material shaped and configured to reflect a substantialportion of a shock front 22 of a specified incident air blast waveenergy 197-I. The shock front is described in conjunction with FIG. 1.In an embodiment, the layer of the first material 2010 of the device2001 includes a layer of a first material shaped and configured toreflect at least 99% of a specified incident air blast wave energy197-I. In an embodiment, the layer of the first material is shaped andconfigured to reflect at least 99% of a shock front of a specifiedincident air blast wave energy. In an embodiment, the layer of the firstmaterial is shaped and configured to reflect at least 90% of a specifiedincident air blast wave energy. In an embodiment, the layer of the firstmaterial is shaped and configured to reflect at least 80% of a shockfront of a specified incident air blast wave energy. In an embodiment,the layer of the first material is shaped and configured to reflect atleast 90% of a specified incident air blast wave energy. In anembodiment, the layer of the first material is shaped and configured toreflect at least 80% of a shock front of a specified incident air blastwave energy. In an embodiment, the layer of the first material is shapedand configured to reflect at least 60% of a specified incident air blastwave energy. In an embodiment, the layer of the first material is shapedand configured to reflect at least 60% of a shock front of a specifiedincident air blast wave energy. In an embodiment, the layer of the firstmaterial is shaped and configured to reflect at least 40% of a specifiedincident air blast wave energy. In an embodiment, the layer of the firstmaterial is shaped and configured to reflect at least 40% of a shockfront of a specified incident air blast wave energy. In an embodiment,the layer of the first material is shaped and configured to reflect atleast 25% of a specified incident air blast wave energy. In anembodiment, the layer of the first material is shaped and configured toreflect at least 25% of a shock front of a specified incident air blastwave energy. In an embodiment, the layer of the first material is shapedand configured to reflect at least 15% of a specified incident air blastwave energy. In an embodiment, the layer of the first material is shapedand configured to reflect at least 15% of a shock front of a specifiedincident air blast wave energy. In an embodiment, the layer of the firstmaterial is shaped and configured to reflect at least 10% of a specifiedincident air blast wave energy. In an embodiment, the layer of the firstmaterial is shaped and configured to reflect at least 10% of a shockfront of a specified incident air blast wave energy. In an embodiment,the layer of the first material is shaped and configured to reflect atleast 5% of a specified incident air blast wave energy. In anembodiment, the layer of the first material is shaped and configured toreflect at least 5% of a shock front of a specified incident air blastwave energy.

In an embodiment, the layer of the first, material is shaped andconfigured to reflect at least 3% of a specified incident air blast waveenergy. In an embodiment, the layer of the first material is shaped andconfigured to reflect at least 3% of a shock front of a specifiedincident air blast wave energy.

In an embodiment, the layer of the first material 2010 has a thickness116 of less than about 3 millimeters (mm). In an embodiment, the layerof the first material has a thickness 116 of less than about 2 mm. In anembodiment, the layer of the first material has a thickness 116 of lessthan about 1 mm.

In an embodiment, the layer of the first material 2010 includes a layerof a first material shaped and configured to reflect a substantialportion of a specified incident air blast wave energy 197-I. The firstmaterial includes at least three reflective-regions. The at least threereflective regions include a first reflective-region 2010A having afirst acoustic impedance Z₁ mismatched to the acoustic impedance of airZ_(A). The at least three reflective regions include a secondreflective-region 2010B having a second acoustic impedance Z₂ less thanthe first acoustic impedance Z₁. The at least three reflective regionsinclude a third reflective-region (not illustrated) having a thirdacoustic impedance Z₃ greater than the second acoustic impedance Z₂. Inan embodiment, the third reflective-region includes thirdreflective-region having a third acoustic impedance Z₃ greater than thesecond acoustic impedance Z₂ and mismatched to the acoustic impedance ofair Z_(A).

In an embodiment, layer of the first material 2010 includes a layer of afirst material shaped and configured to reflect a substantial portion ofa specified incident air blast wave energy 197-I. The first materialincludes at least four reflective-regions. The at least fourreflective-regions include a first reflective-region 2010A having afirst acoustic impedance Z₁ greater than the acoustic impedance of airZ_(A). The at least four reflective-regions include a secondreflective-region 2010B having a second acoustic impedance Z₂. The atleast four reflective-regions include a third reflective-region (notillustrated) having a third acoustic impedance Z₃. The at least fourreflective-regions include a fourth reflective-region (not illustrated)having a third acoustic impedance Z₄. In an embodiment, Z₁>Z₂, Z₃>Z₂,and Z₃>Z₄.

In an embodiment, layer of the first material 2010 includes a layer of afirst material shaped and configured to reflect a substantial portion ofa specified incident air blast wave energy 197-I. The first materialincludes at least six reflective-regions. The at least sixreflective-regions include a first reflective-region 2010A having afirst acoustic impedance Z₁ greater than the acoustic impedance of airZ_(A). The at least six reflective-regions include a secondreflective-region 2010B having a second acoustic impedance Z₂. The atleast six reflective-regions include a third reflective-region (notillustrated) having a third acoustic impedance Z₃. The at least sixreflective-regions include a fourth reflective-region having a fourthacoustic impedance Z₄. The at least six reflective-regions include afifth reflective-region (not illustrated) having a fifth acousticimpedance Z₅. The at least six reflective-regions include a sixthreflective-region (not illustrated) having a sixth acoustic impedanceZ₆. In an embodiment, Z₁>Z₂, Z₃>Z₂, Z₃>Z₄, Z₅>Z₄, and Z₅>Z₆.

FIG. 43 illustrates an embodiment of the layer of the first material2010. The layer of the first material is shaped and configured toreflect a substantial portion of a specified incident air blast waveenergy 197-I. The first material includes an aggregation of at least tworeflective-regions. The aggregation of at least two reflective-regionsinclude first reflective-regions 2010A having a first acoustic impedanceZ₁ mismatched to the acoustic impedance of air Z_(A). The aggregation ofat least two reflective-regions include second reflective-regions 2010Beach having a second acoustic impedance Z₂ less than the first acousticimpedance Z₁. In an embodiment, the aggregation of at least tworeflective-regions includes an aggregation of approximately equalvolumes of at least two reflective-regions.

In an embodiment, the layer of the second material 2020 includes a layerof a second material shaped and configured for wearing proximate to theexterior portion 106 of the human body 105. The second material includesat least two attenuating-regions (not illustrated). The at least twoattenuating-regions include a first attenuating-region (not illustrated)having a first inelastic response to the specified incident air blastwave energy transmitted 197-T through the layer of the first material2010. The at least two attenuating-regions include a secondattenuating-region (not illustrated) having a second inelastic responseto the specified incident air blast wave energy transmitted through thelayer of the first material. For example, the first attenuating-regionand the second attenuating-region may be at least substantially similarto the first attenuating-region 720A and the second attenuating-region720B described in conjunction with FIGS. 22 and 23. For example, thefirst attenuating-region and the second attenuating-region may be atleast substantially similar to the first attenuating-region 1320A andthe second attenuating-region 1320B described in conjunction with FIGS.32 and 33. In an embodiment, the layer of the second material includes alayer of a second material shaped and configured for wearing proximateto the exterior portion of the human body. The second material includesat least two attenuating-regions. The at least two attenuating-regionsinclude a first attenuating-region is shaped and configured to attenuatea first range of overpressures of the specified incident air blast waveenergy transmitted through the layer of the first material utilizing afirst inelastic response. The at least two attenuating-regions include asecond attenuating-region is shaped and configured to attenuate a secondrange of overpressures of the specified incident air blast wave energytransmitted through the layer of the first material utilizing a secondinelastic response. For example, the first attenuating-region and thesecond attenuating-region may be at least substantially similar to thefirst attenuating-region 720A and the second attenuating-region 720Bdescribed in conjunction with FIGS. 22 and 23. For example, the firstattenuating-region and the second attenuating-region may be at leastsubstantially similar to the first attenuating-region 1320A and thesecond attenuating-region 1320B described in conjunction with FIGS. 32and 33.

In an embodiment, the device 2001 includes a spall liner (notillustrated) shaped and configured to restrain at least one fragmentbroken from the layer of the first material 2010 by the specifiedincident air blast wave energy 197-I. For example, the spall liner maybe at least substantially similar to the spall liner 140 described inconjunction with FIGS. 5 and 6. In an embodiment, the layer of the firstmaterial 2010 includes the front surface 2012A and the back surface2014B, the layer of the second material 2020 includes the front surface2022 and the back surface 2024B, and the spall liner 140 includes thefront surface 142 and the back surface 144. In an embodiment, at least aportion of the back surface of the layer of the first material isproximate to at least a portion of the front surface of the spall liner,and at least a portion of the back surface of the spall liner isproximate to the front surface of the layer of the second material. Inan embodiment, at least a portion of the back surface of the layer ofthe first material is proximate to at least a portion of the frontsurface of the layer of the second material, and at least a portion ofthe back surface of the layer of the second material is proximate to atleast a portion of the front surface of the spall liner.

In an embodiment, the device 2001 includes a layer of a ballisticmaterial (not illustrated) shaped and configured to substantiallyattenuate energy of an object impacting the exterior portion 106 of thehuman body 105. For example, the layer of ballistic material may be atleast substantially similar to the layer of ballistic material 170described in conjunction with FIG. 7. In an embodiment, the layer of thefirst material 2010 includes the front surface 2012A and the backsurface 2014B, the layer of the second material 2020 includes the frontsurface 2022 and the back surface 2024, and the layer of ballisticmaterial 170 includes the front surface 172 and the back surface 174. Inan embodiment, at least a portion of the back surface of the layer ofthe ballistic material is proximate to the front surface of the layer ofthe first material, and at least a portion of the back surface of thelayer of the first material is proximate to at least a portion of thefront surface of the second material. In an embodiment, at least aportion of the back surface of the layer of the first material isproximate to the front surface of the layer of the ballistic material,and at least a portion of the back surface of the layer of the ballisticmaterial proximate to at least a portion of the front surface of thelayer of the second material. In an embodiment, at least a portion ofthe back surface of the layer of the second material is proximate to atleast a portion of the front surface of the layer of the ballisticmaterial. In an embodiment, the device includes a retaining apparatus(not illustrated) configured to hold the proximate layer of a firstmaterial and the layer of the second material adjacent to the exteriorportion of a human body.

Returning to FIG. 42. FIG. 42 illustrates an embodiment of the wearableair blast wave energy protection device 2001. The device includes alayer of a first material 2010 shaped and configured to reflect asubstantial portion of a specified incident air blast wave energy 197-I.The first material including at least two reflective-regions. The atleast two reflective-regions include a first reflective-region 2010Ahaving a first acoustic impedance Z₁ mismatched to the acousticimpedance of air Z_(A). The at least two reflective-regions include asecond reflective-region 2010B having a second acoustic impedance Z₂less than the first acoustic impedance Z₁. The device includes a layerof a second material 2020 shaped and configured to attenuate asubstantial portion of the specified incident air blast wave energy197-T transmitted through the layer of the first material utilizing aninelastic response, and shaped and configured for wearing proximate toan exterior portion of a human body. The layer of the first materialincludes a front surface 2012A and a back surface 2014B, and the layerof the second material includes a front surface 2022 and a back surface2024. At least a portion of the back surface of the layer of the firstmaterial is proximate to at least a portion of the front surface of thelayer of the second material. Z₁/Z₂ equals approximately 3. FIG. 43illustrates an alternative embodiment of this embodiment. In thealternative embodiment, the first reflective region includes firstreflective regions 2010A.1 et seq. In the alternative embodiment, thesecond reflective region includes second reflective regions 2010B.1 etseq.

Returning to FIG. 42, FIG. 42 illustrates an embodiment of the wearableair blast wave energy protection device 2001. The device includes alayer of a first material 2010 shaped and configured to reflect asubstantial portion of a specified incident air blast wave energy 197-I.The first material including at least two reflective-regions. The atleast two reflective-regions include a first reflective-region 2010Ahaving a first acoustic impedance Z₁ mismatched to the acousticimpedance of air Z_(A). The at least two reflective-regions include asecond reflective-region 2010B having a second acoustic impedance Z₂less than the first acoustic impedance Z₁. The device includes a layerof a second material 2020 shaped and configured to attenuate asubstantial portion of the specified incident air blast wave energy197-T transmitted through the layer of the first material utilizing aninelastic response, and shaped and configured for wearing proximate toan exterior portion of a human body. The layer of the first materialincludes a front surface 2012A and a back surface 2014B, and the layerof the second material includes a front surface 2022 and a back surface2024. At least a portion of the back surface of the layer of the firstmaterial is proximate to at least a portion of the front surface of thelayer of the second material. Z₁/Z₂ equals approximately 10. FIG. 43illustrates an alternative embodiment of this embodiment. In thealternative embodiment, the first reflective region includes firstreflective regions 2010A.1 et seq. In the alternative embodiment, thesecond reflective region includes second reflective regions 2010B.1 etseq.

FIG. 44 illustrates an example operational flow 2100. After a startoperation, the operational flow includes a first reflection modelingoperation 2110. The first reflection modeling operation includescomputer modeling at least two candidate reflective materials for afirst human-protective and primarily reflective response to a specifiedincident air blast wave energy. The computer modeling of the at leasttwo candidate reflective materials is at least partially based onrespective acoustic impedances of the at least two candidate reflectivematerials to the specified incident air blast wave energy. Therespective acoustic impedances of the at least two candidate reflectivematerials each are substantially mismatched to the acoustic impedance ofair. In an embodiment, the first reflection modeling operation includescomputer modeling at least two candidate reflective materials for afirst advantageous human-protective and primarily reflective response toa specified incident air blast wave energy. In an embodiment, thespecified incident air blast wave energy includes the air blast wave 195produced by the blast event 193 creating an energy propagating acrossspace from the blast event and illustrated as the incident air blastwave energy 197-I described in conjunction with FIG. 2. The operationalflow includes a first reflective material selecting operation 2120. Thefirst reflective material selecting operation includes selecting a firstreflective-region material from the at least two candidate reflectivematerials. The selecting is at least partially based on the computermodeling of the at least two candidate reflective materials. Forexample, the selecting a first reflective-region material may includeselecting the first reflective-region material 2010A described inconjunction with FIG. 42.

The operational flow 2100 includes a second reflection modelingoperation 2130. The second reflection modeling operation includescomputer modeling another at least two candidate reflective materialsfor a second human-protective and primarily reflective response to thespecified incident air blast wave energy. The computer modeling of theanother at least two candidate reflective materials is at leastpartially based on respective acoustic impedances of the at least twocandidate reflective materials to the specified incident air blast waveenergy. In an embodiment, the second reflection modeling operationincludes computer modeling another at least two candidate reflectivematerials for a second advantageous human-protective and primarilyreflective response to a specified incident air blast wave energy. Theoperational flow includes a second reflective material selectionoperation 2140. The second reflective material selection operationincludes selecting a second reflective-region material from the at leasttwo candidate attenuative materials. The selecting is at least partiallybased on the computer modeling of the another at least two candidatereflective materials. For example, the selecting a secondreflective-region material may include selecting the secondreflective-region material 2010B described in conjunction with FIG. 42.

The operational flow 2100 includes an attenuation modeling operation2150. The attenuation modeling operation includes computer modeling atleast two candidate attenuative materials for a third human-protectiveand primarily attenuative response to the specified incident air blastwave energy transmitted through the selected first reflective-regionmaterial and the selected second reflective-region material. Thecomputer modeling of the at least two candidate attenuative materials isat least partially based on respective inelastic responses of the twocandidate attenuative materials to the specified incident air blast waveenergy transmitted through the selected first reflective-region materialor the selected second reflective-region material. The operational flowincludes an attenuative material selecting operation 2160. Theattenuative material selecting operation includes selecting a layer of asecond material from at least two candidate attenuative materials atleast partially based on the computer modeling of at least two candidateattenuative materials. For example, the selecting a layer of a secondmaterial may include selecting the layer of the second material 2020described in conjunction with FIG. 42.

The operational flow 2100 includes a storage operation 2170. The storageoperation includes electronically maintaining informational datacorresponding to the selected first reflective-region material, theselected second reflective-region material, and the selected layer ofthe second material. The operational flow includes an end operation.

FIG. 45 illustrates alternative embodiments of the operational flow 2100of FIG. 44. In an embodiment, the first reflective material selectingoperation 2120 may include at least one alternative embodiment, such asan operation 2122. The operation 2122 includes selecting a firstreflective-region material from the at least two candidate reflectivematerials. The selecting is at least partially based on acomputer-implemented evaluation of the computer modeling of the at leasttwo candidate reflective materials. The second reflective materialselecting operation 2140 includes at least one alternative embodiment,such as an operation 2142. The operation 2142 includes selecting asecond reflective-region material from the at least two candidatereflective materials. The selecting is at least partially based on acomputer-implemented evaluation of the computer modeling of the anotherat least two candidate reflective materials. The attenuative materialselecting operation 2160 may include at least one alternativeembodiment, such as the operation 2162. The operation 2162 includesselecting a layer of a second material from at least two candidateattenuative materials at least partially based on a computer-implementedevaluation of the results of the computer modeling of at least twocandidate attenuative materials.

FIG. 46 illustrates alternative embodiments of the operational flow 2100of FIG. 44. The storage operation 2170 may include at least onealternative embodiment, such as the operation 2172. The operation 2172includes electronically transmitting the informational datacorresponding to the selected first reflective-region material, theselected second reflective-region material, and the selected layer ofthe second material. An alternative embodiment of the operational flowmay include an operation 2180. The operation 2180 includes an operation2182 and an operation 2184. The operation 2182 includes computermodeling at least two candidate arrangements of the selected firstreflective-region material and the selected second reflective-regionmaterial into a layer of a first material providing a fourthhuman-protective and substantial reflective response to the specifiedincident air blast wave energy transmitted through the layer of thefirst material. The operation 2184 includes selecting an arrangement ofthe selected first reflective-region material and the selected secondreflective-region material into the layer of the first material at leastpartially based on a computer-implemented evaluation of the computermodeling of the candidate arrangements of the selected firstreflective-region and the selected second reflective-region. Analternative embodiment of the operational flow may include an operation2190. The operation 2190 includes an operation 2192, an operation 2194,and an operation 2196. The operation 2192 includes computer modeling atleast two candidate junctions between (i) the selected layer of thesecond material and (ii) the selected arrangement of the selected firstreflective-region material and the selected second reflective-regionmaterial. The computer modeling is at least partially based on providinga fifth human-protective response to the specified incident air blastwave energy. For example, the computer modeling may include computermodeling that is at least partially based on providing a fifthadvantageous human-protective response to the specified incident airblast wave energy. The operation 2194 includes selecting a junction atleast partially based on a computer-implemented evaluation of thecomputer modeling of the candidate junctions. The operation 2196includes electronically transmitting the informational datacorresponding to the selected first reflective-region material, theselected second reflective-region material, the selected mannercombining the selected first reflective-region material, the selectedlayer of the second material, and the selected junction.

FIG. 47 illustrates an example operational flow 2200 for manufacturing awearable air blast wave energy protection device. After a startoperation, the operational flow includes a first reflective materialreceiving operation 2210. The first reflective material receivingoperation includes receiving a first reflective-region material shapedand configured to provide a first human-protective and primarilyreflective response to a specified incident air blast wave energy. Thefirst reflective-region material selected at least partially based on afirst acoustic impedance of the first material to the specified incidentair blast wave energy, and on a substantial mismatch between the firstacoustic impedance and the acoustic impedance of air. For example, thereceiving the first reflective-region material may include receiving thefirst reflective-region material 2010A described in conjunction withFIG. 42. The second reflective material receiving operation 2220includes receiving a second reflective-region material shaped andconfigured to provide a second human-protective and primarily reflectiveresponse to the specified incident air blast wave energy. The secondreflective-region material selected at least partially based on a secondacoustic impedance of the first material to the specified incident airblast wave energy, and on having a second acoustic impedancesubstantially less than the first acoustic impedance. For example, thereceiving the second reflective-region material may include receivingthe second reflective-region material 2010B described in conjunctionwith FIG. 42. An arranging operation 2230 includes arranging the firstreflective-region material and the second reflective-region materialinto a layer of a first material providing a third human-protective andsubstantial reflective response to the specified incident air blast waveenergy. For example, the arranging may include arranging the firstreflective material 2010A and the second reflective material 2010B intothe layer of the first material described in conjunction with FIG. 42 or43.

An attenuative material receiving operation 2240 includes receiving alayer of a second material shaped and configured to provide utilizing aninelastic response a fourth human protective and primarily attenuativeresponse to the specified incident air blast wave energy transmittedthrough the layer of the first material. The layer of a second materialis shaped and configured for wearing proximate to an exterior portion ofa human body. For example, the attenuative material receiving operationmay include receiving the layer of the second material 2020 described inconjunction with FIG. 42. A joining operation 2250 includes joining atleast a portion of a back surface of the layer of the first material toat least a portion of a front surface of the layer of the secondmaterial. For example, the joining operation 2250 may include at leastone additional embodiment, such as the operation 2252. The operation2252 includes joining at least a portion of a back surface of the layerof the first material to at least a portion of a front surface of thelayer of the second material. The joining is selected to provide a fifthhuman-protective joining of the layer of the first material and thelayer of the second material to the specified incident air blast waveenergy. The joining is selected at least partially based on an attributeof the first material, an attribute of the second material, or anattribute of the specified incident air blast wave energy.

FIG. 48 illustrates an alternative embodiment of the operational flow2200 of FIG. 47. The operational flow may include at least onealternative embodiment, illustrated as an operation 2260. The operation2260 may include an operation 2262, an operation 2272, an operation2274, or an operation 2276. The operation 2262 includes shaping thelayer of the second material into a configuration suitable for wearingproximate to an exterior portion of a human body. The operation 2262 mayinclude at least one alternative embodiment, such as an operation 2264or an operation 2266. The operation 2264 includes shaping the layer ofthe second material into a physical form configured or user-configurablefor wearing proximate to an exterior portion of a human body. Theoperation 2266 includes shaping the layer of the second material into aphysical form user-configurable for wearing proximate to an exteriorportion of a human body with substantially no air gap between the layerof the second material and the exterior portion of the human body.

The operation 2272 includes attaching at least a portion of the layer ofthe first material or the layer of the second material to a retainingstrap configured to removably secure the layer of the second materialproximate to an exterior portion of the human body. The operation 2274includes attaching at least a portion of the joined layer of the firstmaterial and the layer of the second material to a carrier shaped andconfigured to be secured proximate to an exterior portion of the humanbody. The operation 2276 includes electronically receiving informationaldata corresponding to the first reflective-region material, the secondreflective-region material, the layer of the second material, thearrangement of the layer of a first reflective-region and the layer of asecond reflective-region, or the joining.

FIG. 49 illustrates an example operational flow 2300. The operationalflow includes a start operation. The operational flow includes anoperation 2310. The operation 2310 includes interposing between a blastevent generating an air blast wave energy and an exterior portion of ahuman body a layer of a first material shaped and configured to reflecta substantial portion of a specified incident air blast wave energy. Thefirst material includes at least two reflective-regions. The at leasttwo reflective-regions include a first reflective-region having a firstacoustic impedance Z₁ mismatched to the acoustic impedance of air Z_(A).The at least two reflective-regions include a second reflective-regionhaving a second acoustic impedance Z₂ less than the first acousticimpedance Z₁. The first material includes a first reflective-regionhaving a first acoustic impedance substantially mismatched to theacoustic impedance of air. The first material includes a secondreflective-region having a second acoustic impedance substantially lessthan the first acoustic impedance.

The operation 2310 also includes interposing a layer of a secondmaterial shaped and configured to attenuate a substantial portion of thespecified incident air blast wave energy transmitted through the layerof the first material utilizing an inelastic response. The layer of asecond material is shaped and configured for wearing proximate to anexterior portion of a human body. The layer of the first materialincludes a front surface and a back surface, and the layer of the secondmaterial includes a front surface and a back surface. At least a portionof the back surface of the layer of the first material is proximate toat least a portion of the front surface of the layer of the secondmaterial. The operational flow includes an end operation. For example,the operational flow 2300 may be implemented by interposing the device2001 described in conjunction with FIG. 42 between the incident airblast wave energy 197-I produced by the blast 193 and the exterior bodypart portion 106 of the human body 105.

FIG. 50 illustrates alternative embodiments of the operational flow 2300of FIG. 49. The operational flow may include at least one alternativeembodiment. The at least one alternative embodiment may include anoperation 2320 or an operation 2330. The operation 2320 includessubstantially reflecting a portion the specified incident air blast waveenergy utilizing the layer of the first material. The operation 2330includes substantially attenuating at least a portion of the specifiedincident air blast wave energy transmitted through the layer of thefirst material utilizing an inelastic response of the layer of thesecond material.

FIG. 51 illustrates an environment 2400 that includes example device2401. The device includes the layer of the ballistic material 610described in conjunction with FIG. 21. The layer of ballistic materialis shaped and configured to substantially attenuate energy of an object(not illustrated) impacting the external portion 106 of the human body105. The device 2401 includes the device 2001 described in conjunctionwith FIG. 42 or 2001.1 described in conjunction with FIG. 43. The device2401 includes the layer of the first material 2010 shaped and configuredto reflect a substantial portion of a specified incident air blast waveenergy 197-T. The first material includes at least tworeflective-regions. The at least two reflective-regions include a firstreflective-region 2010A (not illustrated by FIG. 51) having a firstacoustic impedance Z₁ mismatched to the acoustic impedance of air Z_(A).The at least two reflective-regions include a second reflective-region2010B (not illustrated by FIG. 51) having a second acoustic impedance Z₂less than the first acoustic impedance Z₁. The device includes the layerof the second material 2020 shaped and configured to attenuate asubstantial portion of the specified incident air blast wave energytransmitted 197-T through the layer of the first material utilizing aninelastic response. The layer of the second material is shaped andconfigured for wearing proximate to the exterior portion 106 of thehuman body 105.

The layer of the ballistic material 610 includes the front surface 612and the back surface 614. In an embodiment, the front surface may beconsidered an exterior surface of the ballistic material and the backsurface may be considered an interior surface of the ballistic material.The layer of the first material 2010 includes the front surface 2012 andthe back surface 2014. The layer of the second material 2020 includesthe front surface 2022 and the back surface 2024. In an embodiment, atleast a portion of the interior surface of the layer of the ballisticmaterial is proximate to the front surface of the layer of the firstmaterial, and at least a portion of the back surface of the layer of thefirst material is proximate to at least a portion of the front surfaceof the layer of the second material. In an embodiment of the device, atleast a portion of the back surface of the layer of the first materialis proximate to the front surface of the layer of the ballisticmaterial, and at least a portion of the back surface of the layer of theballistic material is proximate to at least a portion of the frontsurface of the layer of the second material (not illustrated). In anembodiment of the device, at least a portion of the back surface of thelayer of the first material is proximate to the front surface of thelayer of a second material, and at least a portion of the back surfaceof the layer of the second material is proximate to at least a portionof the front surface of the layer of the ballistic material (notillustrated).

All references cited herein are hereby incorporated by reference intheir entirety or to the extent their subject matter is not otherwiseinconsistent herewith.

In some embodiments, “configured” includes at least one of designed, setup, shaped, implemented, constructed, or adapted for at least one of aparticular purpose, application, or function.

It will be understood that, in general, terms used herein, andespecially in the appended claims, are generally intended as “open”terms (e.g., the term “including” should be interpreted as “includingbut not limited to,” the term “having” should be interpreted as “havingat least,” the term “includes” should be interpreted as “includes but isnot limited to,” etc.). It will be further understood that if a specificnumber of an introduced claim recitation is intended, such an intentwill be explicitly recited in the claim, and in the absence of suchrecitation no such intent is present. For example, as an aid tounderstanding, the following appended claims may contain usage ofintroductory phrases such as “at least one” or “one or more” tointroduce claim recitations. However, the use of such phrases should notbe construed to imply that the introduction of a claim recitation by theindefinite articles “a” or “an” limits any particular claim containingsuch introduced claim recitation to inventions containing only one suchrecitation, even when the same claim includes the introductory phrases“one or more” or “at least one” and indefinite articles such as “a” or“an” (e.g., “a receiver” should typically be interpreted to mean “atleast one receiver”); the same holds true for the use of definitearticles used to introduce claim recitations. In addition, even if aspecific number of an introduced claim recitation is explicitly recited,it will be recognized that such recitation should typically beinterpreted to mean at least the recited number (e.g., the barerecitation of “at least two chambers,” or “a plurality of chambers,”without other modifiers, typically means at least two chambers).

In those instances where a phrase such as “at least one of A, B, and C,”“at least one of A, B, or C,” or “an [item] selected from the groupconsisting of A, B, and C,” is used, in general such a construction isintended to be disjunctive (e.g., any of these phrases would include butnot be limited to systems that have A alone, B alone, C alone, A and Btogether, A and C together, B and C together, or A, B, and C together,and may further include more than one of A, B, or C, such as A₁, A₂, andC together, A, B₁, B₂, C₁, and C₂ together, or B₁ and B₂ together). Itwill be further understood that virtually any disjunctive word or phrasepresenting two or more alternative terms, whether in the description,claims, or drawings, should be understood to contemplate thepossibilities of including one of the terms, either of the terms, orboth terms. For example, the phrase “A or B” will be understood toinclude the possibilities of “A” or “B” or “A and B.”

The herein described aspects depict different components containedwithin, or connected with, different other components. It is to beunderstood that such depicted architectures are merely examples, andthat in fact many other architectures can be implemented which achievethe same functionality. In a conceptual sense, any arrangement ofcomponents to achieve the same functionality is effectively “associated”such that the desired functionality is achieved. Hence, any twocomponents herein combined to achieve a particular functionality can beseen as “associated with” each other such that the desired functionalityis achieved, irrespective of architectures or intermedial components.Likewise, any two components so associated can also be viewed as being“operably connected,” or “operably coupled,” to each other to achievethe desired functionality. Any two components capable of being soassociated can also be viewed as being “operably couplable” to eachother to achieve the desired functionality. Specific examples ofoperably couplable include but are not limited to physically mateable orphysically interacting components or wirelessly interactable orwirelessly interacting components.

With respect to the appended claims the recited operations therein maygenerally be performed in any order. Also, although various operationalflows are presented in a sequence(s), it should be understood that thevarious operations may be performed in other orders than those which areillustrated, or may be performed concurrently. Examples of suchalternate orderings may include overlapping, interleaved, interrupted,reordered, incremental, preparatory, supplemental, simultaneous,reverse, or other variant orderings, unless context dictates otherwise.Use of “Start,” “End,” “Stop,” or the like blocks in the block diagramsis not intended to indicate a limitation on the beginning or end of anyoperations or functions in the diagram. Such flowcharts or diagrams maybe incorporated into other flowcharts or diagrams where additionalfunctions are performed before or after the functions shown in thediagrams of this application. Furthermore, terms like “responsive to,”“related to,” or other past-tense adjectives are generally not intendedto exclude such variants, unless context dictates otherwise.

While various aspects and embodiments have been disclosed herein, otheraspects and embodiments will be apparent to those skilled in the art.The various aspects and embodiments disclosed herein are for purposes ofillustration and are not intended to be limiting, with the true scopeand spirit being indicated by the following claims.

What is claimed is:
 1. An air blast wave protection device, the devicecomprising: (a) a layer of a first material shaped and configured toreflect a substantial portion of incident air blast wave energycomprising a shock wave originating from a high-order explosive, thelayer of first material having (i) an acoustic impedance substantiallymismatched to the acoustic impedance of air, and (ii) a layer thicknessless than about 2 mm; and (b) a layer of a second material shaped andconfigured to attenuate a substantial portion of the incident air blastwave energy transmitted through the layer of the first materialutilizing an inelastic response, wherein the second material comprises ayield stress to absorb an overpressure greater than about 0.1 bar,wherein the layer of the first material includes a front surface and aback surface, the layer of the second material includes a front surfaceand a back surface, at least a portion of the back surface of the layerof the first material is proximate to at least a portion of the frontsurface of the layer of the second material, and wherein the at leastthe portion of the back surface of the layer of the first material isacoustically coupled to at least the portion of the front surface of thelayer of the second material.
 2. The device of claim 1, wherein thelayer of the first material includes: a layer of a first acousticreflective material shaped and configured to reflect a substantialportion of a incident air blast wave energy, the layer of the firstmaterial having (i) an acoustic impedance substantially mismatched tothe acoustic impedance of air, and (ii) a layer thickness less thanabout 2 mm.
 3. The device of claim 1, wherein the layer of the firstmaterial includes: a layer of a first material having (i) a calculatedreflection coefficient to a incident air blast wave energy of at least50%, and (ii) a layer thickness less than about 2 mm.
 4. The device ofclaim 1, wherein the layer of the first material includes: a layer of afirst material shaped and configured to reflect at least 50% of a shockfront of a incident air blast wave energy and having (i) an acousticimpedance substantially mismatched to the acoustic impedance of air, and(ii) a layer thickness less than about 2 mm.
 5. The device of claim 1,wherein the layer of the first material includes: a layer of a firstmaterial having (i) a calculated reflection coefficient to a incidentair blast wave energy of at least 10%, and (ii) a layer thickness lessthan about 2 mm.
 6. The device of claim 1, wherein the layer of thefirst material includes: a layer of a first material shaped andconfigured to reflect at least 10% of a shock front of a incident airblast wave energy and having (i) an acoustic impedance substantiallymismatched to the acoustic impedance of air, and (ii) a layer thicknessless than about 2 mm.
 7. The device of claim 1, wherein the layer of thefirst material includes: a layer of a first material shaped andconfigured to reflect a substantial portion of a frequency spectrum orprofile of a incident air blast wave energy, the layer of the firstmaterial having (i) an acoustic impedance substantially mismatched tothe acoustic impedance of air, and (ii) a layer thickness less thanabout 2 mm.
 8. The device of claim 1, wherein the layer of the firstmaterial includes: a layer of a first material shaped and configured toreflect a substantial portion of a incident combat high explosive airblast wave energy, the layer of the first material having (i) anacoustic impedance substantially mismatched to the acoustic impedance ofair, and (ii) a layer thickness less than about 2 mm.
 9. The device ofclaim 1, wherein the layer of the first material includes: a layer of afirst material shaped and configured to reflect a substantial portion ofa incident air blast wave energy, the layer of the first material having(i) an acoustic impedance substantially mismatched to the acousticimpedance of air, and (ii) a layer thickness less than about 1.0millimeters.
 10. The device of claim 1, wherein the layer of the firstmaterial includes: a layer of a first material shaped and configured toreflect a substantial portion of a incident air blast wave energy, thelayer of the first material having (i) an acoustic impedancesubstantially mismatched to the acoustic impedance of air, and (ii) alayer thickness less than about 100 microns.
 11. The device of claim 1,wherein the layer of the first material includes: a layer of a firstmaterial including (i) a first reflective-region shaped and configuredto reflect a substantial portion of a incident air blast wave energy,the layer of the first material having (1) an acoustic impedancesubstantially mismatched to the acoustic impedance of air, and (2) alayer thickness less than about 2 millimeters, and (ii) a substrateregion shaped and configured to physically support the firstreflective-region.
 12. The device of claim 1, wherein the layer of thefirst material includes: a layer of a first material shaped andconfigured to reflect a substantial portion of a incident air blast waveenergy and having a layer thickness less than about 2 mm, the layer ofthe first material including a pair of reflective-regions, a firstreflective-region of the pair of regions having a first acousticimpedance Z₁ substantially mismatched to the acoustic impedance of airZ_(A), and a second reflective-region of the pair of regions having asecond acoustic impedance Z₂ substantially dissimilar from the firstacoustic impedance, wherein the specified incident air blast wave energyfirstly-arrives first at the first reflective region and secondlyarrives second at the second acoustic reflective region.
 13. The deviceof claim 12, wherein the layer of the first material includes: a layerof a first material shaped and configured to reflect a substantialportion of a incident air blast wave energy and having a layer thicknessless than about 2 mm, the layer of the first material including a pairof reflective-regions, a first reflective-region of the pair of regionshaving a first acoustic impedance Z₁ substantially mismatched to theacoustic impedance of air Z_(A), and a second reflective-region of thepair of regions having a second acoustic impedance Z₂ substantiallydissimilar from the first acoustic impedance, wherein, the specifiedincident air blast wave energy arrives firstly first at the secondreflective region and arrives secondly second at the second firstreflective region.
 14. The device of claim 1, wherein the layer of thefirst material includes: a layer of a first material shaped andconfigured to reflect a substantial portion of a incident air blast waveenergy and having a layer thickness less than about 2 mm, the layer ofthe first material including at least three reflective-regions, a firstreflective-region of the at least three reflective-regions having afirst acoustic impedance substantially Z₁ mismatched to the acousticimpedance of air Z_(A), a second reflective-region of the at least threereflective-regions having a second acoustic impedance Z₂ substantiallydissimilar from the first acoustic impedance, and a thirdreflective-region of the at least three reflective-regions having athird acoustic impedance Z₃.
 15. The device of claim 14, wherein thelayer of the first material includes: a layer of a first material shapedand configured to reflect a substantial portion of a incident air blastwave energy and having a layer thickness less than about 2 mm, the layerof the first material including at least three reflective-regions, afirst reflective-region of the at least three reflective-regions havinga first acoustic impedance substantially Z₁, mismatched to the acousticimpedance of air Z_(A), a second reflective-region of the at least threereflective-regions having a second acoustic impedance Z₂ substantiallydissimilar from the first acoustic impedance, and a thirdreflective-region of the at least three reflective-regions having athird acoustic impedance Z₃ substantially dissimilar from the secondacoustic impedance Z₂.
 16. The device of claim 1, wherein the layer ofthe first material includes: a layer of a first material shaped andconfigured to reflect a substantial portion of a incident air blast waveenergy and having a layer thickness less than about 2 mm, the layer ofthe first material including at least four reflective-regions, a firstreflective-region of the at least four reflective-regions having a firstacoustic impedance substantially Z₁ mismatched to the acoustic impedanceof air, a second reflective-region of the at least fourreflective-regions having a second acoustic impedance Z₂, a thirdreflective-region of the at least four reflective-regions having a thirdacoustic impedance Z₃, and a fourth reflective-region of the at leastfour reflective-regions having a fourth acoustic impedance Z₄, whereinZ₃/Z₄ at least approximately equals Z₁/Z₂.
 17. The device of claim 1,wherein the layer of the second material includes: a layer of a secondmaterial shaped and configured to attenuate a substantial portion of theincident air blast wave energy transmitted through the layer of thefirst material utilizing an inelastic response, shaped and configuredfor wearing proximate to an exterior portion of a human body, and havinga layer thickness of less than about 5 cm.
 18. The device of claim 1,wherein the layer of the second material includes: a layer of a secondmaterial shaped and configured to attenuate a substantial portion of theincident air blast wave energy transmitted through the layer of thefirst material utilizing an inelastic response, shaped and configuredfor wearing proximate to an exterior portion of a human body, and havinga layer thickness of less than about 1 cm.
 19. The device of claim 1,wherein the layer of the second material includes: a layer of a secondmaterial shaped and configured to attenuate the incident air blast waveenergy transmitted through the layer of the first material by at least 3dB utilizing an inelastic response, and shaped and configured forwearing proximate to an exterior portion of a human body.
 20. The deviceof claim 1, wherein the layer of the second material includes: a layerof a second material shaped and configured to attenuate the incident airblast wave energy transmitted through the layer of the first material byat least 10 dB utilizing an inelastic response, and shaped andconfigured for wearing proximate to an exterior portion of a human body.21. The device of claim 1, wherein the layer of the second materialincludes: a layer of a second material shaped and configured toattenuate the incident air blast wave energy transmitted through thelayer of the first material by at least 30 dB utilizing an inelasticresponse, and shaped and configured for wearing proximate to an exteriorportion of a human body.
 22. The device of claim 1, wherein the layer ofthe second material includes: a layer of a second material shaped andconfigured to attenuate a substantial portion of the incident air blastwave energy transmitted through the layer of the first materialutilizing an inelastic response, and shaped and configured for wearingproximate to an exterior portion of a human body, the inelastic responseof the layer of the second material selected as at least substantiallylikely to provide a human-protective response to the specified incidentair blast wave energy transmitted through the layer of the firstmaterial.
 23. The device of claim 1, wherein the layer of the secondmaterial includes: a layer of a second material shaped and configured toattenuate a substantial portion of the incident air blast wave energytransmitted through the layer of the first material utilizing aninelastic response, and shaped and configured for wearing proximate toan exterior portion of a human body, the inelastic response of the layerof the second material including an inelastic crush response to thespecified incident air blast wave energy transmitted through the layerof the first material.
 24. The device of claim 23, wherein the layer ofthe second material includes: a layer of a second material shaped andconfigured to attenuate a substantial portion of the incident air blastwave energy transmitted through the layer of the first materialutilizing an inelastic response, and shaped and configured for wearingproximate to an exterior portion of a human body, the inelastic responseof the second material including an inelastic crush response to thespecified incident air blast wave energy transmitted through the layerof the first material at an overpressure greater than about 1 bar. 25.The device of claim 1, wherein the layer of the second materialincludes: a layer of a metallic foam material shaped and configured toattenuate a substantial portion of the incident air blast wave energytransmitted through the layer of the first material utilizing aninelastic response, and shaped and configured for wearing proximate toan exterior portion of a human body.
 26. The device of claim 1, whereinthe layer of the second material includes: a layer of a periodiccellular metal material shaped and configured to attenuate a substantialportion of the incident air blast wave energy transmitted through thelayer of the first material utilizing an inelastic response, and shapedand configured for wearing proximate to an exterior portion of a humanbody.
 27. The device of claim 1, wherein the layer of the secondmaterial includes: a layer of a second material shaped and configured toattenuate a substantial portion of the incident air blast wave energytransmitted through the layer of the first material utilizing asingle-use inelastic response, and shaped and configured for wearingproximate to an exterior portion of a human body.
 28. The device ofclaim 1, further comprising: a label indicating use of the device islimited to a single exposure to the incident air blast wave energy. 29.The device of claim 1, further comprising: an indicator configured toprovide a human-perceivable indication that the device has been exposedto an air blast wave energy.
 30. A device comprising; (a) a layer of aballistic material shaped and configured to substantially attenuateenergy of an object impacting an external portion of a human body; (b) alayer of a first material shaped and configured to reflect a substantialportion of incident air blast wave energy comprising a shock waveoriginating from a high-order explosive, the layer of the first materialhaving (i) an acoustic impedance substantially mismatched to theacoustic impedance of air and (ii) a layer thickness less than about 2mm; and (c) a layer of a second material shaped and configured toattenuate a substantial portion of the incident air blast wave energytransmitted through the layer of the first material utilizing aninelastic response, and shaped and configured for wearing proximate to ahuman head, wherein the second material comprises a yield stress toabsorb an overpressure greater than about 0.1 bar, and wherein at leasta portion of a back surface of the layer of the first material isacoustically coupled to at least a portion of a front surface of thelayer of the second material.